WorldWideScience

Sample records for faced multiple constraints

  1. Transparent face recognition in an unconstrained environment using a Sparse representation from multiple still images

    NARCIS (Netherlands)

    B.A.M. Ben Schouten; Dr. Johan Tangelder

    2006-01-01

    In a real-world environment a face detector can be applied to extract multiple face images from multiple video streams without constraints on pose and illumination. The extracted face images will have varying image quality and resolution. Moreover, also the detected faces will not be precisely

  2. Transparent face recognition in an unconstrained environment using a Sparse representation from multiple still images

    NARCIS (Netherlands)

    Tangelder, Johan; Schouten, Ben

    2006-01-01

    In a real-world environment a face detector can be applied to extract multiple face images from multiple video streams without constraints on pose and illumination. The extracted face images will have varying image quality and resolution. Moreover, also the detected faces will not be precisely align

  3. Multiple Face Location Using Motion Information

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Face location is a difficult problem for face recognition and multiple face location is more challenging. In this paper, two new methods are presented for multiple face location via motion analysis techniques. The first method is based on motion segmentation. The authors introduce a new segmentation method by computing optical flow only on the Motion Zero-Crossing Boundary (MZCB) followed by a simple clustering method to segment each person. Then an intuitive but effective location algorithm is applied to locate each face. The second method is derived from the Hough Transform (HT). After modeling a head outline as a curve consisting of circle segments, a modified HT is used to find the center of each face. Finally, the two methods are compared and the future research directions are given.

  4. Constraints Faced by Stakeholders under Agriculture Technology Management Agency (ATMA

    Directory of Open Access Journals (Sweden)

    J. Yoga Narasimhalu Naidu

    2017-09-01

    Full Text Available Agriculture Technology Management Agency (ATMA is a registered society in India with key stakeholders enmeshed with various agricultural activities for sustainable agricultural development in the state, with focus at district level. It is a hotbed for integrating research, extension and marketing activities and decentralizing day-to-day management of the public Agricultural Technology Development and Dissemination System. The present study was carried out in Andhra Pradesh state to explore the constraints faced by the extension functionaries at each level of decentralized management. Moreover, constraints perceived by the farmers with the support of ATMA in realizing their needs were also studied.

  5. Export constraints facing Lesotho-based manufacturing enterprises

    Directory of Open Access Journals (Sweden)

    Motšelisi C. Mokhethi

    2015-02-01

    Full Text Available Orientation: Exporting is preferred by many enterprises as the mode of foreign entry as it requires less commitment of organisational resources and offers flexibility of managerial actions. However, enterprises face a number of challenges when attempting to initiate exports or expand their export operations.Research purpose: This study was undertaken to determine the characteristics and composition of export barriers constraining exporting by Lesotho-based manufacturing enterprises.Motivation for the study: Lesotho is faced with low destination diversity and low diversity in export products.Research design, approach and method: Data was collected from 162 Lesotho-based manufacturing enterprises through a self-administered questionnaire.Main findings: In its findings, the study firstly identified international constraints, distribution constraints and financial constraints as factors constraining exporting. Secondly, it was determined that three exporting constraints, all internal to the enterprise and all related to one factor (namely financial constraint hampered exporting. Lastly, the ANOVA results revealed that the perceptions of export constraints differed according to the enterprise characteristics, enterprise size, ownership and type of industry.Contribution/value-add: With the majority of enterprises in this study being identified as micro-enterprises, the government of Lesotho needs to pay particular attention to addressing the export needs of these enterprises in order to enable them to participate in exporting activities − especially considering that they can play a pivotal role in the alleviation of poverty, job creation and economic rejuvenation.

  6. Learning a sparse representation from multiple still images for on-line face recognition in an unconstrained environment

    NARCIS (Netherlands)

    Tangelder, Johan; Schouten, Ben

    2006-01-01

    In a real-world environment a face detector can be applied to extract multiple face images from multiple video streams without constraints on pose and illumination. The extracted face images will have varying image quality and resolution. Moreover, also the detected faces will not be precisely align

  7. Realistic face modeling based on multiple deformations

    Institute of Scientific and Technical Information of China (English)

    GONG Xun; WANG Guo-yin

    2007-01-01

    On the basis of the assumption that the human face belongs to a linear class, a multiple-deformation model is proposed to recover face shape from a few points on a single 2D image. Compared to the conventional methods, this study has the following advantages. First, the proposed modified 3D sparse deforming model is a noniterative approach that can compute global translation efficiently and accurately. Subsequently, the overfitting problem can be alleviated based on the proposed multiple deformation model. Finally, by keeping the main features, the texture generated is realistic. The comparison results show that this novel method outperforms the existing methods by using ground truth data and that realistic 3D faces can be recovered efficiently from a single photograph.

  8. Multiple Kernel Learning in Fisher Discriminant Analysis for Face Recognition

    Directory of Open Access Journals (Sweden)

    Xiao-Zhang Liu

    2013-02-01

    Full Text Available Recent applications and developments based on support vector machines (SVMs have shown that using multiple kernels instead of a single one can enhance classifier performance. However, there are few reports on performance of the kernel‐based Fisher discriminant analysis (kernel‐based FDA method with multiple kernels. This paper proposes a multiple kernel construction method for kernel‐based FDA. The constructed kernel is a linear combination of several base kernels with a constraint on their weights. By maximizing the margin maximization criterion (MMC, we present an iterative scheme for weight optimization. The experiments on the FERET and CMU PIE face databases show that, our multiple kernel Fisher discriminant analysis (MKFD achieves high recognition performance, compared with single‐kernel‐based FDA. The experiments also show that the constructed kernel relaxes parameter selection for kernel‐based FDA to some extent.

  9. Households facing constraints. Fuel poverty put into context

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, Ute [ISG Business School, Paris (France); Meier, Helena [Koeln Univ. (Germany). Energiewirtschaftliches Inst.

    2014-02-15

    The present paper discusses the concept of fuel poverty taking into account the arbitrages made by households when they are facing economic constraints. Fuel poverty is still lacking a common definition throughout Europe: while the UK and France have (different) official definitions, there is still no definition in a country like Germany, or at the European level. Where definitions exist, they often consider that fuel poor households have high energy needs. The possibility of being fuel poor even without having high energy needs and the various arbitrage possibilities of households - i.e. to under-spend and use too little energy - are not systematically discussed. Our paper tries to fill that gap by putting fuel poverty into the larger context of constraints faced by households. Based on a graphical analysis, it shows that different situations of fuel poverty might occur. It results in the identification of two distinct fuel poverty problems: an ''energy inequality'' problem, reflected by the fact that some households pay disproportionately high energy bills, and an ''energy affordability'' problem that can affect a larger share of the population. It finally explores the two types of fuel poverty for European countries and discusses policy implications.

  10. Multiple Constraints Based Lightpath Provisioning in Optical Networks

    Institute of Scientific and Technical Information of China (English)

    WANGSheng; LILemin

    2005-01-01

    In Wavelength-routed optical Networks, a lightpath can be provisioned only if a path can be found which satisfies multiple constraints while simultaneously achieving optimal primary cost. Where the primary cost can be any metric set by network administrators, and the constraints concerned in optical networks include wavelength continuity constraint and some other impairments in optical domain. In this paper~ the impact of these constraints on the optimal path calculation algorithms is studied, then a unique solving framework is proposed, which treated the whole problem as a Multiple constraint optimal path (MCOP) problem. A novel heuristic for solving MCOP problem is proposed, and its performance is evaluated through extensive simulations.

  11. Borrowing constraints, multiple equilibria and monetary policy

    NARCIS (Netherlands)

    Assenza, T.

    2007-01-01

    The appealing feature of Kiyotaki and Moore's Financial Accelerator model (Kiyotaki and Moore, 1997, 2002) is the linkage of asset price changes and borrowing constraints. This framework therefore is the natural vehicle to explore the net worth channel of the monetary transmission mechanism. In the

  12. Borrowing constraints, multiple equilibria and monetary policy

    NARCIS (Netherlands)

    Assenza, T.

    2007-01-01

    The appealing feature of Kiyotaki and Moore's Financial Accelerator model (Kiyotaki and Moore, 1997, 2002) is the linkage of asset price changes and borrowing constraints. This framework therefore is the natural vehicle to explore the net worth channel of the monetary transmission mechanism. In the

  13. Multiple candidates and multiple constraints based accurate depth estimation for multi-view stereo

    Science.gov (United States)

    Zhang, Chao; Zhou, Fugen; Xue, Bindang

    2017-02-01

    In this paper, we propose a depth estimation method for multi-view image sequence. To enhance the accuracy of dense matching and reduce the inaccurate matching which is produced by inaccurate feature description, we select multiple matching points to build candidate matching sets. Then we compute an optimal depth from a candidate matching set which satisfies multiple constraints (epipolar constraint, similarity constraint and depth consistency constraint). To further increase the accuracy of depth estimation, depth consistency constraint of neighbor pixels is used to filter the inaccurate matching. On this basis, in order to get more complete depth map, depth diffusion is performed by neighbor pixels' depth consistency constraint. Through experiments on the benchmark datasets for multiple view stereo, we demonstrate the superiority of proposed method over the state-of-the-art method in terms of accuracy.

  14. Janus faces of microglia in multiple sclerosis

    NARCIS (Netherlands)

    Sanders, Patricia; De Keyser, Jacques

    2007-01-01

    Multiple sclerosis (MS) is the most common cause of neurological disability in young adults. The disease is characterized by inflammatory reactions, demyelination and axonal loss in the brain, spinal cord and optic nerves. Microglia seem to play an important role in the inflammatory processes in MS,

  15. Face detection based on multiple kernel learning algorithm

    Science.gov (United States)

    Sun, Bo; Cao, Siming; He, Jun; Yu, Lejun

    2016-09-01

    Face detection is important for face localization in face or facial expression recognition, etc. The basic idea is to determine whether there is a face in an image or not, and also its location, size. It can be seen as a binary classification problem, which can be well solved by support vector machine (SVM). Though SVM has strong model generalization ability, it has some limitations, which will be deeply analyzed in the paper. To access them, we study the principle and characteristics of the Multiple Kernel Learning (MKL) and propose a MKL-based face detection algorithm. In the paper, we describe the proposed algorithm in the interdisciplinary research perspective of machine learning and image processing. After analyzing the limitation of describing a face with a single feature, we apply several ones. To fuse them well, we try different kernel functions on different feature. By MKL method, the weight of each single function is determined. Thus, we obtain the face detection model, which is the kernel of the proposed method. Experiments on the public data set and real life face images are performed. We compare the performance of the proposed algorithm with the single kernel-single feature based algorithm and multiple kernels-single feature based algorithm. The effectiveness of the proposed algorithm is illustrated. Keywords: face detection, feature fusion, SVM, MKL

  16. Testing multiple coordination constraints with a novel bimanual visuomotor task.

    Directory of Open Access Journals (Sweden)

    Helene M Sisti

    Full Text Available The acquisition of a new bimanual skill depends on several motor coordination constraints. To date, coordination constraints have often been tested relatively independently of one another, particularly with respect to isofrequency and multifrequency rhythms. Here, we used a new paradigm to test the interaction of multiple coordination constraints. Coordination constraints that were tested included temporal complexity, directionality, muscle grouping, and hand dominance. Twenty-two healthy young adults performed a bimanual dial rotation task that required left and right hand coordination to track a moving target on a computer monitor. Two groups were compared, either with or without four days of practice with augmented visual feedback. Four directional patterns were tested such that both hands moved either rightward (clockwise, leftward (counterclockwise, inward or outward relative to each other. Seven frequency ratios (3∶1, 2∶1, 3∶2, 1∶1, 2∶3. 1∶2, 1∶3 between the left and right hand were introduced. As expected, isofrequency patterns (1∶1 were performed more successfully than multifrequency patterns (non 1∶1. In addition, performance was more accurate when participants were required to move faster with the dominant right hand (1∶3, 1∶2 and 2∶3 than with the non-dominant left hand (3∶1, 2∶1, 3∶2. Interestingly, performance deteriorated as the relative angular velocity between the two hands increased, regardless of whether the required frequency ratio was an integer or non-integer. This contrasted with previous finger tapping research where the integer ratios generally led to less error than the non-integer ratios. We suggest that this is due to the different movement topologies that are required of each paradigm. Overall, we found that this visuomotor task was useful for testing the interaction of multiple coordination constraints as well as the release from these constraints with practice in the presence of

  17. Unified framework of face hallucination across multiple modalities

    Science.gov (United States)

    Ma, Xiang; Liu, Junhui; Li, Wenmin

    2015-02-01

    Face hallucination in a single modality environment has been heavily studied, in real-world environments under multiple modalities is still in its early stage. This paper presents a unified framework to solve face hallucination problem across multiple modalities i.e. different expressions, poses, illuminations. Almost all of the state-of-the-art face superresolution methods only generate a single output with the same modality of the low-resolution input. Our proposed framework is able to generate multiple outputs of different new modalities from only a single low-resolution input. It includes a global transformation with diagonal loading for modeling the mappings among different new facial modalities, and a local position-patch based method with weights compensation for incorporating image details. Experimental results illustrate the superiority of our framework.

  18. A color based face detection system using multiple templates

    Institute of Scientific and Technical Information of China (English)

    王涛; 卜佳俊; 陈纯

    2003-01-01

    A color based system using multiple templates was developed and implemented for detecting human faces in color images. The algorithm consists of three image processing steps. The first step is human skin color statistics. Then it separates skin regions from non-skin regions. After that, it locates the frontal human face(s) within the skin regions. In the first step, 250 skin samples from persons of different ethnicities are used to determine the color distribution of human skin in chromatic color space in order to get a chroma chart showing likelihoods of skin colors. This chroma chart is used to generate, from the original color image, a gray scale image whose gray value at a pixel shows its likelihood of representing the skin. The algorithm uses an adaptive thresholding process to achieve the optimal threshold value for dividing the gray scale image into separate skin regions from non skin regions. Finally, multiple face templates matching is used to determine if a given skin region represents a frontal human face or not. Test of the system with more than 400 color images showed that the resulting detection rate was 83%, which is better than most color-based face detection systems. The average speed for face detection is 0.8 second/image (400×300 pixels) on a Pentium 3 (800MHz) PC.

  19. A color based face detection system using multiple templates

    Institute of Scientific and Technical Information of China (English)

    王涛; 卜佳酸; 陈纯

    2003-01-01

    A color based system using multiple templates was developed and implemented for detecting hu-man faces in color images.The algorithm comsists of three image processing steps.The first step is human skin color statistics.Then it separates skin regions from non-skin regions.After that,it locates the frontal human face(s) within the skin regions.In the first step,250 skin samples from persons of different ethnicities are used to determine the color distribution of human skin in chromatic color space in order to get a chroma chart showing likelihoods of skin colors.This chroma chart is used to generate,from the original color image,a gray scale image whose gray value at a pixel shows its likelihood of representing the shin,The algorithm uses an adaptive thresholding process to achieve the optimal threshold value for dividing the gray scale image into sep-arate skin regions from non skin regions.Finally,multiple face templates matching is used to determine if a given skin region represents a frontal human face or not.Test of the system with more than 400 color images showed that the resulting detection rate was 83%,which is better than most colou-based face detection sys-tems.The average speed for face detection is 0.8 second/image(400×300pixels) on a Pentium 3(800MHz) PC.

  20. Multiple pyogenic granulomas on the face after landmine injury.

    Science.gov (United States)

    Bakan, Vedat; Aliagaoglu, Cihangir; Yildiz, Abdullah; Emsen, Murat

    2008-01-01

    In this report, we present a 13-year-old male patient with multiple pyogenic granulomas (PG) on the face after landmine injury. To the best of our knowledge, PG after landmine injury has not been reported previously. The case has been reported in view of its rarity and its etiology.

  1. Channel Coding over Multiple Coherence Blocks with Queueing Constraints

    CERN Document Server

    Qiao, Deli; Velipasalar, Senem

    2010-01-01

    This paper investigates the performance of wireless systems that employ finite-blocklength channel codes for transmission and operate under queueing constraints in the form of limitations on buffer overflow probabilities. A block fading model, in which fading stays constant in each coherence block and change independently between blocks, is considered. It is assumed that channel coding is performed over multiple coherence blocks. An approximate lower bound on the transmission rate is obtained from Feintein's Lemma. This lower bound is considered as the service rate and is incorporated into the effective capacity formulation, which characterizes the maximum constant arrival rate that can be supported under statistical queuing constraints. Performances of variable-rate and fixed-rate transmissions are studied. The optimum error probability for variable rate transmission and the optimum coding rate for fixed rate transmission are shown to be unique. Moreover, the tradeoff between the throughput and the number of...

  2. Cosmological constraints from multiple tracers in spectroscopic surveys

    CERN Document Server

    Alarcon, Alex; Gaztañaga, Enrique

    2016-01-01

    We use the Fisher matrix formalism to study the expansion and growth history of the Universe using galaxy clustering with 2D angular cross-correlation tomography in spectroscopic or high resolution photometric redshift surveys. The radial information is contained in the cross correlations between narrow redshift bins. We show how multiple tracers with redshift space distortions cancel sample variance and arbitrarily improve the constraints on the dark energy equation of state $\\omega(z)$ and the growth parameter $\\gamma$ in the noiseless limit. The improvement for multiple tracers quickly increases with the bias difference between the tracers, up to a factor $\\sim4$ in $\\text{FoM}_{\\gamma\\omega}$. We model a magnitude limited survey with realistic density and bias using a conditional luminosity function, finding a factor 1.3-9.0 improvement in $\\text{FoM}_{\\gamma\\omega}$ -- depending on global density -- with a split in a halo mass proxy. Partly overlapping redshift bins improve the constraints in multiple tr...

  3. Attitude synchronization for multiple spacecraft with input constraints

    Directory of Open Access Journals (Sweden)

    Lyu Jianting

    2014-04-01

    Full Text Available The attitude synchronization problem for multiple spacecraft with input constraints is investigated in this paper. Two distributed control laws are presented and analyzed. First, by introducing bounded function, a distributed asymptotically stable control law is proposed. Such a control scheme can guarantee attitude synchronization and the control inputs of each spacecraft can be a priori bounded regardless of the number of its neighbors. Then, based on graph theory, homogeneous method, and Lyapunov stability theory, a distributed finite-time control law is designed. Rigorous proof shows that attitude synchronization of multiple spacecraft can be achieved in finite time, and the control scheme satisfies input saturation requirement. Finally, numerical simulations are presented to demonstrate the effectiveness and feasibility of the proposed schemes.

  4. Exploring manifold structure of face images via multiple graphs

    KAUST Repository

    Alghamdi, Masheal

    2013-12-24

    Geometric structure in the data provides important information for face image recognition and classification tasks. Graph regularized non-negative matrix factorization (GrNMF) performs well in this task. However, it is sensitive to the parameters selection. Wang et al. proposed multiple graph regularized non-negative matrix factorization (MultiGrNMF) to solve the parameter selection problem by testing it on medical images. In this paper, we introduce the MultiGrNMF algorithm in the context of still face Image classification, and conduct a comparative study of NMF, GrNMF, and MultiGrNMF using two well-known face databases. Experimental results show that MultiGrNMF outperforms NMF and GrNMF for most cases.

  5. The Effect of Fearful Expressions on Multiple Face Tracking

    Directory of Open Access Journals (Sweden)

    Hongjun Jin

    2015-07-01

    Full Text Available How does the visual system realize dynamic tracking? This topic has become popular within cognitive science in recent years. The classical theory argues that multiple object tracking is accomplished via pre-attention visual indexes as part of a cognitively impenetrable low-level visual system. The present research aimed to investigate whether and how tracking processes are influenced by facial expressions that convey abundant social information about one’s mental state and situated environment. The results showed that participants tracked fearful faces more effectively than neutral faces. However, this advantage was only present under the low-attentional load condition, and distractor face emotion did not impact tracking performance. These findings imply that visual tracking is not driven entirely by low-level vision and encapsulated by high-level representations; rather, that facial expressions, a kind of social information, are able to influence dynamic tracking. Furthermore, the effect of fearful expressions on multiple face tracking is mediated by the availability of attentional resources.

  6. An efficient method for generalized linear multiplicative programming problem with multiplicative constraints

    OpenAIRE

    Zhao, Yingfeng; Liu, Sanyang

    2016-01-01

    We present a practical branch and bound algorithm for globally solving generalized linear multiplicative programming problem with multiplicative constraints. To solve the problem, a relaxation programming problem which is equivalent to a linear programming is proposed by utilizing a new two-phase relaxation technique. In the algorithm, lower and upper bounds are simultaneously obtained by solving some linear relaxation programming problems. Global convergence has been proved and results of so...

  7. The Multiple Vehicle TSP with Time Windows and Equity Constraints over a Multiple Day Horizon

    OpenAIRE

    1996-01-01

    This paper considers the multiple vehicle traveling salesman problem cast over a multiple day routing scenario, with time windows and equity constraints. It develops an optimal column generation procedure and heuristic variations which solve test problems derived from the overnight delivery business. Extensive empirical testing indicates the judicious chose of a few routes for each day can incorporate equity at little or no additional cost. Federal Express Naval Postgraduate School Re...

  8. Optimization and Analysis on Trajectory with Multiple Constraints for Hypersonic Air-vehicle

    Directory of Open Access Journals (Sweden)

    Wei Changzhu

    2015-01-01

    Full Text Available The trajectory optimization technology is one of the key technologies for hypersonic air-vehicle. There are multiple constraints in the process of hypersonic flight, such as uncertainty of flight environment, thermal current, dynamic pressure and overload. The trajectory optimization of hypersonic air-vehicle is facing with a great challenge. This article studies the direct shooting method, the Gauss pseudo spectral method and sequential gradient-restoration algorithm, among which the direct shooting method simply makes the control variables discrete in the time domain, and obtains the status value by explicit numerical integration; Gauss pseudo spectral method makes the status variable and control variable discrete in a series of Gauss points, and constructs multinomial to approximate to the status and control variable by taking the discrete points as the nodes; sequential gradient-restoration algorithm uses iteration to meet the constraints and minimize the increment of initial value of control and status variable in order to constantly approximate to the optimal solution on condition that the constraints meet first order approximation. Finally this article conducts a numerical simulation by taking the diving segment of hypersonic air-vehicle as an example for comparative analysis on those three algorithms respectively from, such as, the initial value selection, constraint handling, convergence speed and calculation accuracy. The simulation result indicates Gauss pseudo spectral method is a method with fairly good comprehensive performance.

  9. Influence of socioeconomic factors on production constraints faced by indigenous chicken producers in South Africa.

    Science.gov (United States)

    Mtileni, Bohani Joseph; Muchadeyi, Farai C; Maiwashe, Azwihangwisi; Chimonyo, Michael; Mapiye, Cletos; Dzama, Kennedy

    2013-01-01

    Individual interviews were conducted in 137 households using semi-structured questionnaires to determine the influence of socioeconomic factors on production constraints faced by indigenous chicken producers in the rural areas of South Africa. The major constraints to village chicken production were mortality (95 % of the households) followed by feed shortage (85 %) and low chicken sales (72 %). The logistic regression model showed that households that owned imported/crossbred chickens practiced extensive production system without housing structures and did not have vaccines were more likely to experience high levels of chicken mortality. Poor and youth-headed households with no supplements and vaccines had high probability of Newcastle disease. The probability of a household to experience chicken feed shortage was lower in households that owned indigenous chickens than those that owned imported/crossbred chickens (odds ratio, 11.68; 95 % confidence interval, 1.19-27.44). Youth-headed households that had small flocks and no access to veterinary services were not likely to sell chickens. It was concluded that gender, age, wealth status, production system, chicken flock size, type of chicken breed owned, accessibility of veterinary services, availability of supplements, vaccines and shelter influence village chicken farmer's production constraints such as feed availability, chicken mortality, prevalence of diseases and chicken sales.

  10. Ecophysiological response of Adelie penguins facing an experimental increase in breeding constraints.

    Science.gov (United States)

    Beaulieu, M; Spée, M; Lazin, D; Ropert-Coudert, Y; le Maho, Y; Ancel, A; Raclot, T

    2010-01-01

    Foraging strategies play a key role in breeding effort. Little is known, however, about their connection with hormonal and nutritional states, especially when breeding constraints vary. Here, we experimentally increased foraging costs and thus breeding constraints by handicapping Adélie penguins (Pygoscelis adeliae) with dummy devices representing 3-4% of the penguins' cross-sectional area. We examined food-related stress (via plasma corticosterone concentration) and nutritional state (via metabolite levels). Concurrently, we investigated the use of ecological niches via the isotopic signature of red blood cells indicating the trophic position (delta(15)N) and the spatial distribution (delta(13)C) of penguins. Handicapped birds performed approximately 70% longer foraging trips and lost approximately 60% more body mass than controls and their partners. However, corticosterone levels and the nutritional state were unchanged. The isotopic signature revealed that males and females differed in their foraging behaviour: upper trophic levels contributed more in the males' diet, who foraged in more pelagic areas. Handicapped and partner birds adopted the same strategy at sea: a shift towards higher delta(13)C values suggested that they foraged in more coastal areas than controls. This change in foraging decisions may optimize feeding time by decreasing travelling time. This may partly compensate for the presumed lower foraging efficiency of handicapped birds and for the energetic debt of their partners who had to fast approximately 70% longer on the nest. We propose that this flexible use of ecological niches may allow birds facing increased breeding constraints to avoid chronic stress and to minimize the impact on their body condition.

  11. Optimality criteria solution strategies in multiple constraint design optimization

    Science.gov (United States)

    Levy, R.; Parzynski, W.

    1981-01-01

    Procedures and solution strategies are described to solve the conventional structural optimization problem using the Lagrange multiplier technique. The multipliers, obtained through solution of an auxiliary nonlinear optimization problem, lead to optimality criteria to determine the design variables. It is shown that this procedure is essentially equivalent to an alternative formulation using a dual method Lagrangian function objective. Although mathematical formulations are straight-forward, successful applications and computational efficiency depend upon execution procedure strategies. Strategies examined, with application examples, include selection of active constraints, move limits, line search procedures, and side constraint boundaries.

  12. Combination of multiple measurement cues for visual face tracking

    DEFF Research Database (Denmark)

    Katsarakis, Nikolaos; Pnevmatikakis, Aristodemos; Tan, Zheng-Hua

    2014-01-01

    Visual face tracking is an important building block for all intelligent living and working spaces, as it is able to locate persons without any human intervention or the need for the users to carry sensors on themselves. In this paper we present a novel face tracking system built on a particle...

  13. Constraints on Contact Angles for Multiple Phases in Thermodynamic Equilibrium.

    Science.gov (United States)

    Blunt, Martin J.

    2001-07-01

    For three or more fluid phases in thermodynamic equilibrium and in contact with a solid surface, the Young equation can be used to find relations between the contact angles for different pairs of fluids. For an n-fluid-phase system, n(n-1)/2 contact angles can be defined, but there are (n-1)(n-2)/2 constraints between them, leaving only n-1 independent values of the contact angle. These constraints are very powerful in limiting and determining possible types of wetting behavior. The consequences are discussed for three- and four-phase flow. They have important applications for the understanding of gas injection processes in petroleum reservoirs. Copyright 2001 Academic Press.

  14. Randomized Solutions to Convex Programs with Multiple Chance Constraints

    CERN Document Server

    Schildbach, Georg; Morari, Manfred

    2012-01-01

    Optimization is ubiquitous in modern problems of engineering and science, and in many cases it comes along with some uncertainty about the system or model underlying the problem at hand. A large variety of approaches for handling uncertainty have been proposed in the areas of robust and stochastic optimization, of which the formulation of chance-constraints has proven to be an appropriate concept for many practical applications. Yet chance-constrained optimization programs are generally difficult to solve. The scenario approach provides an intuitive way of approximating the solution to chance-constrained optimization programs, based on finding an optimal solution under a finite number of sampled outcomes of the uncertainty (`scenarios'). A key merit of this approach is that it neither requires knowledge of an uncertainty set, as it is common in robust optimization, nor of a probability distribution, as it is usually assumed in stochastic optimization. Recent research has obtained a strong theoretical foundati...

  15. Multiple deep convolutional neural networks averaging for face alignment

    Science.gov (United States)

    Zhang, Shaohua; Yang, Hua; Yin, Zhouping

    2015-05-01

    Face alignment is critical for face recognition, and the deep learning-based method shows promise for solving such issues, given that competitive results are achieved on benchmarks with additional benefits, such as dispensing with handcrafted features and initial shape. However, most existing deep learning-based approaches are complicated and quite time-consuming during training. We propose a compact face alignment method for fast training without decreasing its accuracy. Rectified linear unit is employed, which allows all networks approximately five times faster convergence than a tanh neuron. An eight learnable layer deep convolutional neural network (DCNN) based on local response normalization and a padding convolutional layer (PCL) is designed to provide reliable initial values during prediction. A model combination scheme is presented to further reduce errors, while showing that only two network architectures and hyperparameter selection procedures are required in our approach. A three-level cascaded system is ultimately built based on the DCNNs and model combination mode. Extensive experiments validate the effectiveness of our method and demonstrate comparable accuracy with state-of-the-art methods on BioID, labeled face parts in the wild, and Helen datasets.

  16. Nonlinear and cooperative control of multiple hovercraft with input constraints

    OpenAIRE

    Dunbar, William B.; Olfati-Saber, Reza; Richard M Murray

    2003-01-01

    In this paper, we introduce an approach for distributed nonlinear control of multiple hovercraft-type underactuated vehicles with bounded and unidirectional inputs. First, a bounded nonlinear controller is given for stabilization and tracking of a single vehicle, using a cascade backstepping method. Then, this controller is combined with a distributed gradient-based control for multi-vehicle formation stabilization using formation potential functions previously constructed. The vehicles are u...

  17. A face recognition algorithm based on multiple individual discriminative models

    DEFF Research Database (Denmark)

    Fagertun, Jens; Gomez, David Delgado; Ersbøll, Bjarne Kjær

    2005-01-01

    Abstract—In this paper, a novel algorithm for facial recognition is proposed. The technique combines the color texture and geometrical configuration provided by face images. Landmarks and pixel intensities are used by Principal Component Analysis and Fisher Linear Discriminant Analysis to associate...... facial image corresponds to a person in the database. Each projection is also able to visualizing the most discriminative facial features of the person associated to the projection. The performance of the proposed method is tested in two experiments. Results point out the proposed technique...... as an accurate and robust tool for facial identification and unknown detection....

  18. Face image analysis using a multiple features fitting strategy

    OpenAIRE

    Romdhani, Sami

    2005-01-01

    The main contribution of this thesis is a novel algorithm for fitting a Three-Dimensional Morphable Model of faces to a 2D input image. This fitting algorithm enables the estimation of the 3D shape, the texture, the 3D pose and the light direction from a single input image. Generally, the algorithms tackling the problem of 3D shape estimation from image data use only the pixels intensity as input to drive the estimation process. This was previously achieved using either a simple model, such as ...

  19. Beauty is better pursued: effects of attractiveness in multiple-face tracking.

    Science.gov (United States)

    Liu, Chang Hong; Chen, Wenfeng

    2012-01-01

    Using the multiple-object tracking paradigm, this study examines how spontaneous appraisal for facial beauty affects distributed attention to multiple faces in dynamic displays. Observers tracked attractive faces more effectively than unattractive faces in this task. Tracking performance was only affected by target attractiveness, suggesting an absence of appraisal for distractor attractiveness. Attractive male faces also produced stronger binding of face identity and location for female participants. Together, the results suggest that facial attractiveness was appraised during tracking even though this was task irrelevant. Contrary to the theory that multiple-object tracking is driven by encapsulated low-level vision, our results show that the content of target representation is not only penetrable by social cognition but also modulates the course of tracking operations.

  20. Multiple opposing constraints govern chromosome interactions during meiosis.

    Directory of Open Access Journals (Sweden)

    Doris Y Lui

    Full Text Available Homolog pairing and crossing over during meiosis I prophase is required for accurate chromosome segregation to form euploid gametes. The repair of Spo11-induced double-strand breaks (DSB using a homologous chromosome template is a major driver of pairing in many species, including fungi, plants, and mammals. Inappropriate pairing and crossing over at ectopic loci can lead to chromosome rearrangements and aneuploidy. How (or if inappropriate ectopic interactions are disrupted in favor of allelic interactions is not clear. Here we used an in vivo "collision" assay in budding yeast to test the contributions of cohesion and the organization and motion of chromosomes in the nucleus on promoting or antagonizing interactions between allelic and ectopic loci at interstitial chromosome sites. We found that deletion of the cohesin subunit Rec8, but not other chromosome axis proteins (e.g. Red1, Hop1, or Mek1, caused an increase in homolog-nonspecific chromosome interaction, even in the absence of Spo11. This effect was partially suppressed by expression of the mitotic cohesin paralog Scc1/Mdc1, implicating Rec8's role in cohesion rather than axis integrity in preventing nonspecific chromosome interactions. Disruption of telomere-led motion by treating cells with the actin polymerization inhibitor Latrunculin B (Lat B elevated nonspecific collisions in rec8Δ spo11Δ. Next, using a visual homolog-pairing assay, we found that the delay in homolog pairing in mutants defective for telomere-led chromosome motion (ndj1Δ or csm4Δ is enhanced in Lat B-treated cells, implicating actin in more than one process promoting homolog juxtaposition. We suggest that multiple, independent contributions of actin, cohesin, and telomere function are integrated to promote stable homolog-specific interactions and to destabilize weak nonspecific interactions by modulating the elastic spring-like properties of chromosomes.

  1. Polysemy and the Taxonomic Constraint: Children's Representation of Words That Label Multiple Kinds

    Science.gov (United States)

    Srinivasan, Mahesh; Snedeker, Jesse

    2014-01-01

    How do children resolve the problem of indeterminacy when learning a new word? By one account, children adopt a "taxonomic assumption" and expect the word to denote only members of a particular taxonomic category. According to one version of this constraint, young children should represent polysemous words that label multiple kinds--for…

  2. Research on the configuration design method of heterogeneous constellation reconstruction under the multiple objective and multiple constraint

    Science.gov (United States)

    Zhao, Shuang; Xu, Yanli; Dai, Huayu

    2017-05-01

    Aiming at the problem of configuration design of heterogeneous constellation reconstruction, a design method of heterogeneous constellation reconstruction based on multi objective and multi constraints is proposed. At first, the concept of heterogeneous constellation is defined. Secondly, the heterogeneous constellation reconstruction methods were analyzed, and then the two typical existing design methods of reconstruction, phase position uniformity method and reconstruction configuration design method based on optimization algorithm are summarized. The advantages and shortcomings of different reconstruction configuration design methods are compared, finally the heterogeneous constellation reconstruction configuration design is currently facing problems are analyzed and put forward the thinking about the reconstruction index system of heterogeneous constellation and the selection of optimal variables and the establishment of constraints in the optimization design of the configuration.

  3. Multiple constraints QoS multicast routing optimization algorithm in MANET based on GA

    Institute of Scientific and Technical Information of China (English)

    Baolin Sun; Shangchao Pi; Chao Gui; Yue Zeng; Bing Yan; Wenxiang Wang; Qianqing Qin

    2008-01-01

    Usually multiple quality of service (QoS) guarantees are required in most multicast applications. This paper presents a multiple constraints algorithm for multicast traffic engineering in mobile ad hoc networks (MANET). The proposed algorithm is a new version of multiple constraints QoS multicast routing optimization algorithm in MANET based on genetic algorithm (MQMGA). The proposed MQMGA can optimize the maximum link utilization, the cost of the multicast tree, the selection of the long-life path, the average delay and the maximum end-to-end delay. Experimental result shows that the approach is efficient, has promising performance in multicast traffic engineering and for evaluating the route stability in dynamic mobile networks.

  4. Nonlinear control of multiple spacecraft formation flying using the constraint forces in Lagrangian systems

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Getting inspiration from the constraint forces in the classical mechanics, we presented the nonlinear control method of multiple spacecraft formation flying to accurately keep the desired formation arrays. Considering nonlinearity and perturbation, we changed the question of the formation array control to the Lagrange equations with the holonomic constraints and the differential algebraic equations (DAE), and developed the nonlinear control for design of the follower spacecraft tracking control laws by solving the DAE. Because of using the idea of the constraint forces, this approach can adequately utilize the characteristic of the dynamic equations, i.e., the space natural forces, and accurately keep the arbitrary formation array. Simulation results of the circular formation keeping with the linear and nonlinear dynamical equations were included to illuminate the control performance.

  5. Transmission Strategies in Multiple Access Fading Channels with Statistical QoS Constraints

    CERN Document Server

    Qiao, Deli; Velipasalar, Senem

    2010-01-01

    Effective capacity, which provides the maximum constant arrival rate that a given service process can support while satisfying statistical delay constraints, is analyzed in a multiuser scenario. In particular, the effective capacity region of fading multiple access channels (MAC) in the presence of quality of service (QoS) constraints is studied. Perfect channel side information (CSI) is assumed to be available at both the transmitters and the receiver. It is initially assumed the transmitters send the information at a fixed power level and hence do not employ power control policies. Under this assumption, the performance achieved by superposition coding with successive decoding techniques is investigated. It is shown that varying the decoding order with respect to the channel states can significantly increase the achievable throughput region. In the two-user case, the optimal decoding strategy is determined for the scenario in which the users have the same QoS constraints. The performance of orthogonal trans...

  6. GNSS Precise Kinematic Positioning for Multiple Kinematic Stations Based on A Priori Distance Constraints

    Directory of Open Access Journals (Sweden)

    Kaifei He

    2016-04-01

    Full Text Available When applying the Global Navigation Satellite System (GNSS for precise kinematic positioning in airborne and shipborne gravimetry, multiple GNSS receiving equipment is often fixed mounted on the kinematic platform carrying the gravimetry instrumentation. Thus, the distances among these GNSS antennas are known and invariant. This information can be used to improve the accuracy and reliability of the state estimates. For this purpose, the known distances between the antennas are applied as a priori constraints within the state parameters adjustment. These constraints are introduced in such a way that their accuracy is taken into account. To test this approach, GNSS data of a Baltic Sea shipborne gravimetric campaign have been used. The results of our study show that an application of distance constraints improves the accuracy of the GNSS kinematic positioning, for example, by about 4 mm for the radial component.

  7. GNSS Precise Kinematic Positioning for Multiple Kinematic Stations Based on A Priori Distance Constraints.

    Science.gov (United States)

    He, Kaifei; Xu, Tianhe; Förste, Christoph; Petrovic, Svetozar; Barthelmes, Franz; Jiang, Nan; Flechtner, Frank

    2016-04-01

    When applying the Global Navigation Satellite System (GNSS) for precise kinematic positioning in airborne and shipborne gravimetry, multiple GNSS receiving equipment is often fixed mounted on the kinematic platform carrying the gravimetry instrumentation. Thus, the distances among these GNSS antennas are known and invariant. This information can be used to improve the accuracy and reliability of the state estimates. For this purpose, the known distances between the antennas are applied as a priori constraints within the state parameters adjustment. These constraints are introduced in such a way that their accuracy is taken into account. To test this approach, GNSS data of a Baltic Sea shipborne gravimetric campaign have been used. The results of our study show that an application of distance constraints improves the accuracy of the GNSS kinematic positioning, for example, by about 4 mm for the radial component.

  8. Bi-Level Multi-criteria Multiple Constraint Level Optimization MODELS and Its Application

    Directory of Open Access Journals (Sweden)

    Lei Zhao

    2013-05-01

    Full Text Available Because oil field development system is a large hierarchical and uncertain system,    this paper uses the theory of bi-level programming and multi-criteria multiple constraint level ( to formulate a new oilfield measure structural optimization model which is bi-level multiple objectives and multiple constraint level nonlinear programming, and present a new method to solve the bi-level programming whose lower is multiple objectives nonlinear programming, whose upper is linear programming. The result of this model not only may feed back to the comprehensive information of measures output distribution optimization to decision-makers as a whole, but also can provide decision makers oil field exploitation contingency planning to deal with changed resource constraint level. The case study shows that the result fitting calculation by the model is coincide with the historical data of oil field, the model is correct and effective. Moreover this research may provide a reliable new method for oil field development optimal decision-making.

  9. On the capacity of multiple cognitive links through common relay under spectrum-sharing constraints

    KAUST Repository

    Yang, Yuli

    2011-06-01

    In this paper, we consider an underlay cognitive relaying network consisting of multiple secondary users and introduce a cooperative transmission protocol using a common relay to help with the communications between all secondary source-destination pairs for higher throughput and lower realization complexity. A whole relay-assisted transmission procedure is composed of multiple access phase and broadcast phase, where the relay is equipped with multiple antennas, and the secondary sources and destinations are single-antenna nodes. Considering the spectrum-sharing constraints on the secondary sources and the relay, we analyze the capacity behaviors of the underlay cognitive relaying network under study. The corresponding numerical results provide a convenient tool for the presented network design and substantiate a distinguishing feature of introduced design in that multiple secondary users\\' communications do not rely on multiple relays, hence allowing for a more efficient use of the radio resources. © 2011 IEEE.

  10. Applications of multiple-constraint matrix updates to the optimal control of large structures

    Science.gov (United States)

    Smith, S. W.; Walcott, B. L.

    1992-01-01

    Low-authority control or vibration suppression in large, flexible space structures can be formulated as a linear feedback control problem requiring computation of displacement and velocity feedback gain matrices. To ensure stability in the uncontrolled modes, these gain matrices must be symmetric and positive definite. In this paper, efficient computation of symmetric, positive-definite feedback gain matrices is accomplished through the use of multiple-constraint matrix update techniques originally developed for structural identification applications. Two systems were used to illustrate the application: a simple spring-mass system and a planar truss. From these demonstrations, use of this multiple-constraint technique is seen to provide a straightforward approach for computing the low-authority gains.

  11. Supply constraints : Australia and Canada coal industry face logistics and capacity challenges

    Energy Technology Data Exchange (ETDEWEB)

    Borsato, J.

    2010-09-15

    Australia and Canada are benefiting from a global increase in coal consumption, but face challenges regarding coal and coal export capacity. Coal is Australia's biggest export commodity, accounting for over 50 percent of world coking coal exports, with almost 75 percent of those exports destined for Asian markets, primarily Japan. However, the number of ships delayed at Australian ports hit a record of 223 bulk carriers in early 2010. Compared to Canada, Australia faces greater logistical issues getting coal into port and onto ships at its 9 loading terminals. Two of Canada's 3 major shipping terminals, Westshore and Neptune, have some additional capacity. Its third terminal, Ridley Island, has considerable potential to carry more coal. With 98 percent of all coal moved by rail in Australia, rail issues also hinder growth. A national approach to planning freight transport on both roads and rail is being developed. While infrastructure issues remain the single greatest barrier to export growth for Australia's coal sector, Canada's most immediate issues pertain to mine permitting and mine-site expansion. In 2009, Canada exported 28 million tonnes of coal, 90 percent of it metallurgical. With approximately 70 million tonnes of annual production, mostly in British Columbia and Alberta, coal remains the number one commodity in Canada carried by rails and shipped from ports. 1 fig.

  12. Selective constraints on amino acids estimated by a mechanistic codon substitution model with multiple nucleotide changes.

    Directory of Open Access Journals (Sweden)

    Sanzo Miyazawa

    Full Text Available BACKGROUND: Empirical substitution matrices represent the average tendencies of substitutions over various protein families by sacrificing gene-level resolution. We develop a codon-based model, in which mutational tendencies of codon, a genetic code, and the strength of selective constraints against amino acid replacements can be tailored to a given gene. First, selective constraints averaged over proteins are estimated by maximizing the likelihood of each 1-PAM matrix of empirical amino acid (JTT, WAG, and LG and codon (KHG substitution matrices. Then, selective constraints specific to given proteins are approximated as a linear function of those estimated from the empirical substitution matrices. RESULTS: Akaike information criterion (AIC values indicate that a model allowing multiple nucleotide changes fits the empirical substitution matrices significantly better. Also, the ML estimates of transition-transversion bias obtained from these empirical matrices are not so large as previously estimated. The selective constraints are characteristic of proteins rather than species. However, their relative strengths among amino acid pairs can be approximated not to depend very much on protein families but amino acid pairs, because the present model, in which selective constraints are approximated to be a linear function of those estimated from the JTT/WAG/LG/KHG matrices, can provide a good fit to other empirical substitution matrices including cpREV for chloroplast proteins and mtREV for vertebrate mitochondrial proteins. CONCLUSIONS/SIGNIFICANCE: The present codon-based model with the ML estimates of selective constraints and with adjustable mutation rates of nucleotide would be useful as a simple substitution model in ML and Bayesian inferences of molecular phylogenetic trees, and enables us to obtain biologically meaningful information at both nucleotide and amino acid levels from codon and protein sequences.

  13. Minimum weight design of rotorcraft blades with multiple frequency and stress constraints

    Science.gov (United States)

    Chattopadhyay, Aditi; Walsh, Joanne L.

    1988-01-01

    Minimum weight designs of helicopter rotor blades with constraints on multiple coupled flap-lag natural frequencies are studied. Constraints are imposed on the minimum value of the blade autorotational inertia to ensure sufficient rotary inertia to autorotate in case of engine failure and on stresses to guard against structural failure due to blade centrifugal forces. Design variables include blade taper ratio, dimensions of the box beam located inside the airfoil and magnitudes of nonstructural weights. The program CAMRAD is used for the blade modal analysis; the program CONMIN is used for the optimization. A linear approximation involving Taylor series expansion is used to reduce the analysis effort. The procedure contains a sensitivity analysis consisting of analytical derivatives for objective function and constraints on autorotational inertia and stresses. Central finite difference derivatives are used for frequency constraints. Optimal designs are obtained for both rectangular and tapered blades. Using this method, it is possible to design a rotor blade with reduced weight, when compared to a baseline blade, while satisfying all the imposed design requirements.

  14. Multiple Treatments of Pediatric Constraint-Induced Movement Therapy (pCIMT): A Clinical Cohort Study.

    Science.gov (United States)

    DeLuca, Stephanie C; Ramey, Sharon Landesman; Trucks, Mary Rebekah; Wallace, Dorian Ainsworth

    2015-01-01

    Pediatric constraint-induced movement therapy (pCIMT) is one of the most efficacious treatments for children with cerebral palsy (CP). Distinctive components of pCIMT include constraint of the less impaired upper extremity (UE), high-intensity therapy for the more impaired UE (≥ 3 hr/day, many days per week, for multiple weeks), use of shaping techniques combined with repetitive task practice, and bimanual transfer. A critical issue is whether multiple treatments of pCIMT produce additional benefit. In a clinical cohort (mean age = 31 mo) of 28 children with asymmetrical CP whose parents sought multiple pCIMT treatments, the children gained a mean of 13.2 (standard deviation [SD] = 4.2) new functional skills after Treatment 1; Treatment 2 produced a mean of 7.3 (SD = 4.7) new skills; and Treatment 3, 6.5 (SD = 4.2). These findings support the conclusion that multiple pCIMT treatments can produce clinically important functional gains for children with hemiparetic CP.

  15. 3D face recognition based on multiple keypoint descriptors and sparse representation.

    Directory of Open Access Journals (Sweden)

    Lin Zhang

    Full Text Available Recent years have witnessed a growing interest in developing methods for 3D face recognition. However, 3D scans often suffer from the problems of missing parts, large facial expressions, and occlusions. To be useful in real-world applications, a 3D face recognition approach should be able to handle these challenges. In this paper, we propose a novel general approach to deal with the 3D face recognition problem by making use of multiple keypoint descriptors (MKD and the sparse representation-based classification (SRC. We call the proposed method 3DMKDSRC for short. Specifically, with 3DMKDSRC, each 3D face scan is represented as a set of descriptor vectors extracted from keypoints by meshSIFT. Descriptor vectors of gallery samples form the gallery dictionary. Given a probe 3D face scan, its descriptors are extracted at first and then its identity can be determined by using a multitask SRC. The proposed 3DMKDSRC approach does not require the pre-alignment between two face scans and is quite robust to the problems of missing data, occlusions and expressions. Its superiority over the other leading 3D face recognition schemes has been corroborated by extensive experiments conducted on three benchmark databases, Bosphorus, GavabDB, and FRGC2.0. The Matlab source code for 3DMKDSRC and the related evaluation results are publicly available at http://sse.tongji.edu.cn/linzhang/3dmkdsrcface/3dmkdsrc.htm.

  16. Approximating the Gaussian Multiple Description Rate Region Under Symmetric Distortion Constraints

    CERN Document Server

    Tian, Chao; Diggavi, Suhas N

    2008-01-01

    We consider multiple description coding for the Gaussian source with K descriptions under the symmetric mean squared error distortion constraints, and provide an approximate characterization of the rate region. We show that the rate region can be sandwiched between two polytopes, between which the gap can be upper bounded by constants dependent on the number of descriptions, but independent of the exact distortion constraints. Underlying this result is an exact characterization of the lossless multi-level diversity source coding problem: a lossless counterpart of the MD problem. This connection provides a polytopic template for the inner and outer bounds to the rate region. In order to establish the outer bound, we generalize Ozarow's technique to introduce a strategic expansion of the original probability space by more than one random variables. For the symmetric rate case with any number of descriptions, we show that the gap between the upper bound and the lower bound for the individual description rate is ...

  17. Robust fuzzy control subject to state variance and passivity constraints for perturbed nonlinear systems with multiplicative noises.

    Science.gov (United States)

    Chang, Wen-Jer; Huang, Bo-Jyun

    2014-11-01

    The multi-constrained robust fuzzy control problem is investigated in this paper for perturbed continuous-time nonlinear stochastic systems. The nonlinear system considered in this paper is represented by a Takagi-Sugeno fuzzy model with perturbations and state multiplicative noises. The multiple performance constraints considered in this paper include stability, passivity and individual state variance constraints. The Lyapunov stability theory is employed to derive sufficient conditions to achieve the above performance constraints. By solving these sufficient conditions, the contribution of this paper is to develop a parallel distributed compensation based robust fuzzy control approach to satisfy multiple performance constraints for perturbed nonlinear systems with multiplicative noises. At last, a numerical example for the control of perturbed inverted pendulum system is provided to illustrate the applicability and effectiveness of the proposed multi-constrained robust fuzzy control method.

  18. Multiple-Constraint-Aware RWA Algorithms Based on a Comprehensive Evaluation Model: Use in Wavelength-Switched Optical Networks%Multiple-Constraint-Aware RWA Algorithms Based on a Comprehensive Evaluation Model: Use in Wavelength-Switched Optical Networks

    Institute of Scientific and Technical Information of China (English)

    Hui Yang; YongliZhao; Shanguo Huang; Dajiang Wang; Xuping Cao; Xuefeng Lin

    2012-01-01

    Because of explosive growth in Internet traffic and high complexity of heterogeneous networks, improving the routing and wavelength assignment (RWA) algorithm in underlying optical networks has become very important. Where there are multiple links between different the node pairs, a traditional wavelength-assignment algorithm may be invalid for a wavelength-switched optical networks (WSON) that has directional blocking constraints. Also, impairments in network nodes and subsequent degradation of optical signals may cause modulation failure in the optical network. In this paper, we propose an RWA algorithm based on a novel evaluation model for a WSQN that has multiple constraints. The algorithm includes comprehensive evaluation model (CEM) and directional blocking constraint RWA based on CEM (DB-RWA). Diverse constraints are abstracted into various constraint conditions in order to better assign routing and wavelength. We propose using the novel CEM to optimize routing according to an assessed value of constraints on transmission performance. This eliminates the effects of physical transmission impairments in a WSON. DB-RWA based on CEM abstracts directional blocking conditions in multiple links between network nodes into directional blocking constraints. It also satisfies rigorous network specifications and provides flexibility, scalability, and first-fit rate for the backbone, especially in multiple links between WSON nodes.

  19. Multiple shooting applied to robust reservoir control optimization including output constraints on coherent risk measures

    DEFF Research Database (Denmark)

    Codas, Andrés; Hanssen, Kristian G.; Foss, Bjarne

    2017-01-01

    The production life of oil reservoirs starts under significant uncertainty regarding the actual economical return of the recovery process due to the lack of oil field data. Consequently, investors and operators make management decisions based on a limited and uncertain description of the reservoir....... In this work, we propose a new formulation for robust optimization of reservoir well controls. It is inspired by the multiple shooting (MS) method which permits a broad range of parallelization opportunities and output constraint handling. This formulation exploits coherent risk measures, a concept...

  20. On the Achievable Throughput Region of Multiple-Access Fading Channels with QoS Constraints

    CERN Document Server

    Qiao, Deli; Velipasalar, Senem

    2009-01-01

    Effective capacity, which provides the maximum constant arrival rate that a given service process can support while satisfying statistical delay constraints, is analyzed in a multiuser scenario. In particular, we study the achievable effective capacity region of the users in multiaccess fading channels (MAC) in the presence of quality of service (QoS) constraints. We assume that channel side information (CSI) is available at both the transmitters and the receiver, and superposition coding technique with successive decoding is used. When the power is fixed at the transmitters, we show that varying the decoding order with respect to the channel state can significantly increase the achievable throughput region. For a two-user case, we obtain the optimal decoding strategy when the users have the same QoS constraints. Meanwhile, it is shown that time-division multiple-access (TDMA) can achieve better performance than superposition coding with fixed successive decoding order at the receiver side for certain QoS con...

  1. Zero-Point Energy Constraint for Unimolecular Dissociation Reactions. Giving Trajectories Multiple Chances To Dissociate Correctly.

    Science.gov (United States)

    Paul, Amit K; Hase, William L

    2016-01-28

    A zero-point energy (ZPE) constraint model is proposed for classical trajectory simulations of unimolecular decomposition and applied to CH4* → H + CH3 decomposition. With this model trajectories are not allowed to dissociate unless they have ZPE in the CH3 product. If not, they are returned to the CH4* region of phase space and, if necessary, given additional opportunities to dissociate with ZPE. The lifetime for dissociation of an individual trajectory is the time it takes to dissociate with ZPE in CH3, including multiple possible returns to CH4*. With this ZPE constraint the dissociation of CH4* is exponential in time as expected for intrinsic RRKM dynamics and the resulting rate constant is in good agreement with the harmonic quantum value of RRKM theory. In contrast, a model that discards trajectories without ZPE in the reaction products gives a CH4* → H + CH3 rate constant that agrees with the classical and not quantum RRKM value. The rate constant for the purely classical simulation indicates that anharmonicity may be important and the rate constant from the ZPE constrained classical trajectory simulation may not represent the complete anharmonicity of the RRKM quantum dynamics. The ZPE constraint model proposed here is compared with previous models for restricting ZPE flow in intramolecular dynamics, and connecting product and reactant/product quantum energy levels in chemical dynamics simulations.

  2. A Novel Kalman Filter with State Constraint Approach for the Integration of Multiple Pedestrian Navigation Systems

    Directory of Open Access Journals (Sweden)

    Haiyu Lan

    2015-07-01

    Full Text Available Numerous solutions/methods to solve the existing problems of pedestrian navigation/localization have been proposed in the last decade by both industrial and academic researchers. However, to date there are still major challenges for a single pedestrian navigation system (PNS to operate continuously, robustly, and seamlessly in all indoor and outdoor environments. In this paper, a novel method for pedestrian navigation approach to fuse the information from two separate PNSs is proposed. When both systems are used at the same time by a specific user, a nonlinear inequality constraint between the two systems’ navigation estimates always exists. Through exploring this constraint information, a novel filtering technique named Kalman filter with state constraint is used to diminish the positioning errors of both systems. The proposed method was tested by fusing the navigation information from two different PNSs, one is the foot-mounted inertial navigation system (INS mechanization-based system, the other PNS is a navigation device that is mounted on the user’s upper body, and adopting the pedestrian dead reckoning (PDR mechanization for navigation update. Monte Carlo simulations and real field experiments show that the proposed method for the integration of multiple PNSs could improve each PNS’ navigation performance.

  3. APPLICATION OF BINARY DESCRIPTORS TO MULTIPLE FACE TRACKING IN VIDEO SURVEILLANCE SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. L. Oleinik

    2016-07-01

    Full Text Available Subject of Research. The paper deals with the problem of multiple face tracking in a video stream. The primary application of the implemented tracking system is the automatic video surveillance. The particular operating conditions of surveillance cameras are taken into account in order to increase the efficiency of the system in comparison to existing general-purpose analogs. Method. The developed system is comprised of two subsystems: detector and tracker. The tracking subsystem does not depend on the detector, and thus various face detection methods can be used. Furthermore, only a small portion of frames is processed by the detector in this structure, substantially improving the operation rate. The tracking algorithm is based on BRIEF binary descriptors that are computed very efficiently on modern processor architectures. Main Results. The system is implemented in C++ and the experiments on the processing rate and quality evaluation are carried out. MOTA and MOTP metrics are used for tracking quality measurement. The experiments demonstrated the four-fold processing rate gain in comparison to the baseline implementation that processes every video frame with the detector. The tracking quality is on the adequate level when compared to the baseline. Practical Relevance. The developed system can be used with various face detectors (including slow ones to create a fully functional high-speed multiple face tracking solution. The algorithm is easy to implement and optimize, so it may be applied not only in full-scale video surveillance systems, but also in embedded solutions integrated directly into cameras.

  4. Enhanced understanding of the terrestrial carbon cycle through multiple constraints in model-data-integration approaches

    Science.gov (United States)

    Carvalhais, N.; Forkel, M.; Oijen, M. V.; Keenan, T. F.; MacBean, N.; Rolinski, S.; Peylin, P. P.; Schuermann, G. J.; Zaehle, S.; Reichstein, M.

    2015-12-01

    The representation of exchanges of carbon, water and energy between the land surface and the atmosphere still reveals significant model limitations in explaining temporal and spatial variability. Despite agreement between models for contemporaneous periods, prognostic simulations reveal a strong between-model divergence regarding the role of the land surface in the global carbon cycle. The integration of multiple data-streams in inverse modelling approaches for parameterization and model evaluation, ultimately leads to model improvement. Here we explore multiple-constraint approaches ranging from in situ to regional and global spatial scales. Constraints include stocks and fluxes of water and carbon. We show that integrating multiple datasets contributes to a better representation of ecosystem dynamics in different models, from forest and dynamic vegetation models to land surface schemes. At site scale, model-data comparisons reveal substantial differences in the modelled temporal dynamics of carbon stocks and turnover times and their relationships with climate, especially at annual scales. Inter-annual variability remains a problem for all models, even after parameter optimization. At regional and global scales, the integration of multiple data-streams to constrain albedo, phenology and primary productivity patterns yields a significant improvement in regional simulations of vegetation dynamics, from seasons to longer-term trends. The role of environmental controls and vegetation dynamics in explaining recent trends in the amplitude of the seasonal cycle of atmospheric CO2 is evaluated using an improved dynamic vegetation model. We conclude by identifying major challenges in model-data-integration: to explore the information content in longer time series; avoid confounding effects of missing processes on parameter estimation; set up cost functions for multivariate-data integration; quantification of uncertainties arising from data bias, model structure, and

  5. Multiple scales combined principle component analysis deep learning network for face recognition

    Science.gov (United States)

    Tian, Lei; Fan, Chunxiao; Ming, Yue

    2016-03-01

    It is well known that higher level features can represent the abstract semantics of original data. We propose a multiple scales combined deep learning network to learn a set of high-level feature representations through each stage of convolutional neural network for face recognition, which is named as multiscaled principle component analysis (PCA) Network (MS-PCANet). There are two main differences between our model and the traditional deep learning network. On the one hand, we get the prefixed filter kernels by learning the principal component of images' patches using PCA, nonlinearly process the convolutional results by using simple binary hashing, and pool them using spatial pyramid pooling method. On the other hand, in our model, the output features of several stages are fed to the classifier. The purpose of combining feature representations from multiple stages is to provide multiscaled features to the classifier, since the features in the latter stage are more global and invariant than those in the early stage. Therefore, our MS-PCANet feature compactly encodes both holistic abstract information and local specific information. Extensive experimental results show our MS-PCANet model can efficiently extract high-level feature presentations and outperform state-of-the-art face/expression recognition methods on multiple modalities benchmark face-related datasets.

  6. Dynamical mass and multiplicity constraints on co-orbital bodies around stars

    CERN Document Server

    Veras, Dimitri; Gaensicke, Boris T

    2016-01-01

    Objects transiting near or within the disruption radius of both main sequence (e.g. KOI 1843) and white dwarf (WD 1145+017) stars are now known. Upon fragmentation or disintegration, these planets or asteroids may produce co-orbital configurations of nearly equal-mass objects. However, as evidenced by the co-orbital objects detected by transit photometry in the WD 1145+017 system, these bodies are largely unconstrained in size, mass, and total number (multiplicity). Motivated by potential future similar discoveries, we perform N-body simulations to demonstrate if and how debris masses and multiplicity may be bounded due to second-to-minute deviations and the resulting accumulated phase shifts in the osculating orbital period amongst multiple co-orbital equal point masses. We establish robust lower and upper mass bounds as a function of orbital period deviation, but find the constraints on multiplicity to be weak. We also quantify the fuzzy instability boundary, and show that mutual collisions occur in less th...

  7. The protective role of ethnic identity for urban adolescent males facing multiple stressors.

    Science.gov (United States)

    Williams, Joanna L; Aiyer, Sophie M; Durkee, Myles I; Tolan, Patrick H

    2014-10-01

    Having a connection to one's ethnic heritage is considered a protective factor in the face of discrimination; however, it is unclear whether the protective effects are persistent across multiple stressors. Furthermore, the dimensions of ethnic identity that reflect group pride/connection (affirmation) and exploration of the meaning of group membership (achievement) may operate differently in the face of stress. The present study examined the moderating role of ethnic identity affirmation and achievement on concurrent and longitudinal relationships between exposure to stress (discrimination, family hardship, exposure to violence) and antisocial behavior in a sample of 256 Black and Latino male youth (70% Black) living in low-income urban neighborhoods. Using regression analysis, concurrent associations were examined at age 18, and longitudinal associations were tested 18 months later. We found that, among youth experiencing discrimination, high levels of achievement and low levels of affirmation predicted greater aggressive behavior and delinquency. Low affirmation also predicted more criminal offending in the face of discrimination. The two dimensions operated similarly in the context of family stress, in which case high levels of affirmation and achievement predicted lower levels of antisocial behavior. The findings suggest a differential role of the two dimensions of ethnic identity with respect to discrimination; furthermore, the coping skills that may be promoted as youth make meaning of their ethnic group membership may serve as cultural assets in the face of family stress.

  8. Designing a mixture experiment when the components are subject to a nonlinear multiple-component constraint

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Greg F.; Cooley, Scott K.; Vienna, John D.; Crum, Jarrod V.

    2015-12-14

    This article presents a case study of developing an experimental design for a constrained mixture experiment when the experimental region is defined by single-component constraints (SCCs), linear multiple-component constraints (MCCs), and a nonlinear MCC. Traditional methods and software for designing constrained mixture experiments with SCCs and linear MCCs are not directly applicable because of the nonlinear MCC. A modification of existing methodology to account for the nonlinear MCC was developed and is described in this article. The case study involves a 15-component nuclear waste glass example in which SO3 is one of the components. SO3 has a solubility limit in glass that depends on the composition of the balance of the glass. A goal was to design the experiment so that SO3 would not exceed its predicted solubility limit for any of the experimental glasses. The SO3 solubility limit had previously been modeled by a partial quadratic mixture (PQM) model expressed in the relative proportions of the 14 other components. The PQM model was used to construct a nonlinear MCC in terms of all 15 components. In addition, there were SCCs and linear MCCs. This article discusses the waste glass example and how a layered design was generated to (i) account for the SCCs, linear MCCs, and nonlinear MCC and (ii) meet the goals of the study.

  9. Memory State Feedback RMPC for Multiple Time-Delayed Uncertain Linear Systems with Input Constraints

    Directory of Open Access Journals (Sweden)

    Wei-Wei Qin

    2014-01-01

    Full Text Available This paper focuses on the problem of asymptotic stabilization for a class of discrete-time multiple time-delayed uncertain linear systems with input constraints. Then, based on the predictive control principle of receding horizon optimization, a delayed state dependent quadratic function is considered for incorporating MPC problem formulation. By developing a memory state feedback controller, the information of the delayed plant states can be taken into full consideration. The MPC problem is formulated to minimize the upper bound of infinite horizon cost that satisfies the sufficient conditions. Then, based on the Lyapunov-Krasovskii function, a delay-dependent sufficient condition in terms of linear matrix inequality (LMI can be derived to design a robust MPC algorithm. Finally, the digital simulation results prove availability of the proposed method.

  10. Optimal design for an end face engagement worm gear with multiple worm-wheel meshing

    Science.gov (United States)

    Deng, Xingqiao; Zhu, Weibing; Chen, Yonghong; Chen, Shouan; Wang, Jinge

    2017-01-01

    To solve the problem for lacking a special mechanical transmission that could provide multiple outputs with high transmission efficiency and good lubrication in the modern industrial, a novel worm gear, named end face engagement worm gear, with multiple worm-wheel meshing is proposed for the first time. The essential parameters for the worm gear are optimized to enhance lubrication and meshing properties. Moreover, analysis of variance(ANOVA) is applied to determine the optimum levels and to determine the influence of parameters. The ANOVA results show that the novel end face engagement worm gear with multiple worm wheels provides high lubrication(the lubrication angle is more than 89°) and meshing performance(the induce normal curvature is less than 0.0002 mm-1). The interaction between center distance and roller slant distance most strongly influences the lubrication angle(contributed 51.6%), followed by the parameters of center distance(contributed 25.0%), roller slant distance(contributed 16.4%), tooth angle of gear, gear ratio, and roller radius. In addition, roller radius most strongly influences the induced normal curvature(contributed 39.4%), followed by roller slant distance(contributed 15.2%), tooth angle of the gear(contributed 9.0%), center distance, and gear ratio. The proposed worm gear helps to enrich the no-backlash high precision worm drive and the optimal design method can provide a useful reference on performance improvement of other worm gear.

  11. 带有多个可转化约束的频繁项集挖掘算法%Mining Frequent Item Sets with Multiple Convertible Constraints

    Institute of Scientific and Technical Information of China (English)

    宋宝莉; 张帮华; 何炎祥; 朱骁峰

    2003-01-01

    Recent work has highlighted the importance of the constraint-based mining paradigm in the context of frequent item sets, associations, correlations. Some research has raised the notion "convertible constraints", and this method can push some constraints into the mining algorithm which essentially can''t be pushed. This article has introduced a multiple convertible constraints mining algorithm, which analyzes the constraints by taking advantage of a sample database and then decides a optimal method to process data mining

  12. Young women facing multiple and intersecting stressors of modernity, gender orders and youth.

    Science.gov (United States)

    Wiklund, Maria; Bengs, Carita; Malmgren-Olsson, Eva-Britt; Ohman, Ann

    2010-11-01

    This article aims to explore stressors experienced by Swedish adolescent girls and young women, specifically understood in relation to social context and gender theory. Interviews were conducted with 40 young Swedish women, aged 16-25 years, who had sought help at a youth health centre for stress problems. Using qualitative content analysis we identified three clusters of stressors: "the stressors of modernity", "the stressors of gendered orders", and "the stressors of youth". The results revealed that multiple and intersecting discourse-shaped stressors and demands connected to essential life spheres contribute not only to experiences of distress but also to feelings of constraint. Gendered individualism and healthism proved to be essential in understanding the young women's experienced stress. Failing social support from adults, gendered demands and responsibility taking were also illuminated. This calls for a broad contextualized and gender-sensitive approach to young women's stress and health problems. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Multiple independent constraints help resolve net ecosystem carbon exchange under nutrient limitation

    Science.gov (United States)

    Thornton, P. E.; Metcalfe, D.; Oren, R.; Ricciuto, D. M.

    2014-12-01

    The magnitude, spatial distribution, and variability of land net ecosystem exchange of carbon (NEE) are important determinants of the trajectory of atmospheric carbon dioxide concentration. Independent observational constraints provide important clues regarding NEE and its component fluxes, with information available at multiple spatial scales: from cells, to leaves, to entire organisms and collections of organisms, to complex landscapes and up to continental and global scales. Experimental manipulations, ecosystem observations, and process modeling all suggest that the components of NEE (photosynthetic gains, and respiration and other losses) are controlled in part by the availability of mineral nutrients, and that nutrient limitation is a common condition in many biomes. Experimental and observational constraints at different spatial scales provide a complex and sometimes puzzling picture of the nature and degree of influence of nutrient availability on carbon cycle processes. Photosynthetic rates assessed at the cellular and leaf scales are often higher than the observed accumulation of carbon in plant and soil pools would suggest. We infer that a down-regulation process intervenes between carbon uptake and plant growth under conditions of nutrient limitation, and several down-regulation mechanisms have been hypothesized and tested. A recent evaluation of two alternative hypotheses for down-regulation in the light of whole-plant level flux estimates indicates that some plants take up and store extra carbon, releasing it to the environment again on short time scales. The mechanism of release, either as additional autotrophic respiration or as exudation belowground is unclear, but has important consequences for long-term ecosystem state and response to climate change signals. Global-scale constraints from atmospheric concentration and isotopic composition data help to resolve this question, ultimately focusing attention on land use fluxes as the most uncertain

  14. Absence of multiple local minima effects in intensity modulated optimization with dose-volume constraints

    Energy Technology Data Exchange (ETDEWEB)

    Llacer, Jorge [EC Engineering Consultants, LLC 130, Forest Hill Drive, Los Gatos, CA (United States); Deasy, Joseph O [Department of Radiation Oncology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO (United States); Bortfeld, Thomas R [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, 30 Fruit Street, Boston, MA (United States); Solberg, Timothy D [Department of Radiation Oncology, University of California, Los Angeles, CA (United States); Promberger, Claus [BrainLAB AG, Ammerthalstrasse 8, 85551 Heimstetten (Germany)

    2003-01-21

    This paper reports on the analysis of intensity modulated radiation treatment optimization problems in the presence of non-convex feasible parameter spaces caused by the specification of dose-volume constraints for the organs-at-risk (OARs). The main aim was to determine whether the presence of those non-convex spaces affects the optimization of clinical cases in any significant way. This was done in two phases: (1) Using a carefully designed two-dimensional mathematical phantom that exhibits two controllable minima and with randomly initialized beamlet weights, we developed a methodology for exploring the nature of the convergence characteristics of quadratic cost function optimizations (deterministic or stochastic). The methodology is based on observing the statistical behaviour of the residual cost at the end of optimizations in which the stopping criterion is progressively more demanding and carrying out those optimizations to very small error changes per iteration. (2) Seven clinical cases were then analysed with dose-volume constraints that are stronger than originally used in the clinic. The clinical cases are two prostate cases differently posed, a meningioma case, two head-and-neck cases, a spleen case and a spine case. Of the 14 different sets of optimizations (with and without the specification of maximum doses allowed for the OARs), 12 fail to show any effect due to the existence of non-convex feasible spaces. The remaining two sets of optimizations show evidence of multiple minima in the solutions, but those minima are very close to each other in cost and the resulting treatment plans are practically identical, as measured by the quality of the dose-volume histograms (DVHs). We discuss the differences between fluence maps resulting from those similar treatment plans. We provide a possible reason for the observed results and conclude that, although the study is necessarily limited, the annealing characteristics of a simulated annealing method may not be

  15. Absence of multiple local minima effects in intensity modulated optimization with dose-volume constraints

    Science.gov (United States)

    Llacer, Jorge; Deasy, Joseph O.; Bortfeld, Thomas R.; Solberg, Timothy D.; Promberger, Claus

    2003-01-01

    This paper reports on the analysis of intensity modulated radiation treatment optimization problems in the presence of non-convex feasible parameter spaces caused by the specification of dose-volume constraints for the organs-at-risk (OARs). The main aim was to determine whether the presence of those non-convex spaces affects the optimization of clinical cases in any significant way. This was done in two phases: (1) Using a carefully designed two-dimensional mathematical phantom that exhibits two controllable minima and with randomly initialized beamlet weights, we developed a methodology for exploring the nature of the convergence characteristics of quadratic cost function optimizations (deterministic or stochastic). The methodology is based on observing the statistical behaviour of the residual cost at the end of optimizations in which the stopping criterion is progressively more demanding and carrying out those optimizations to very small error changes per iteration. (2) Seven clinical cases were then analysed with dose-volume constraints that are stronger than originally used in the clinic. The clinical cases are two prostate cases differently posed, a meningioma case, two head-and-neck cases, a spleen case and a spine case. Of the 14 different sets of optimizations (with and without the specification of maximum doses allowed for the OARs), 12 fail to show any effect due to the existence of non-convex feasible spaces. The remaining two sets of optimizations show evidence of multiple minima in the solutions, but those minima are very close to each other in cost and the resulting treatment plans are practically identical, as measured by the quality of the dose-volume histograms (DVHs). We discuss the differences between fluence maps resulting from those similar treatment plans. We provide a possible reason for the observed results and conclude that, although the study is necessarily limited, the annealing characteristics of a simulated annealing method may not be

  16. Multiple goals and time constraints: perceived impact on physicians' performance of evidence-based behaviours

    Directory of Open Access Journals (Sweden)

    Francis Jillian J

    2009-11-01

    Full Text Available Abstract Background Behavioural approaches to knowledge translation inform interventions to improve healthcare. However, such approaches often focus on a single behaviour without considering that health professionals perform multiple behaviours in pursuit of multiple goals in a given clinical context. In resource-limited consultations, performing these other goal-directed behaviours may influence optimal performance of a particular evidence-based behaviour. This study aimed to investigate whether a multiple goal-directed behaviour perspective might inform implementation research beyond single-behaviour approaches. Methods We conducted theory-based semi-structured interviews with 12 general medical practitioners (GPs in Scotland on their views regarding two focal clinical behaviours--providing physical activity (PA advice and prescribing to reduce blood pressure (BP to Results Most GPs reported strong intention to prescribe to reduce BP but expressed reasons why they would not. Intention to provide PA advice was variable. Most GPs reported that time constraints and patient preference detrimentally affected their control over providing PA advice and prescribing to reduce BP, respectively. Most GPs perceived many of their other goal-directed behaviours as interfering with providing PA advice, while fewer GPs reported goal-directed behaviours that interfere with prescribing to reduce BP. Providing PA advice and prescribing to reduce BP were perceived to be facilitated by similar diabetes-related behaviours (e.g., discussing cholesterol. While providing PA advice was perceived to be mainly facilitated by providing other lifestyle-related clinical advice (e.g., talking about weight, BP prescribing was reported as facilitated by pursuing ongoing standard consultation-related goals (e.g., clearly structuring the consultation. Conclusion GPs readily relate their other goal-directed behaviours with having a facilitating and interfering influence on their

  17. Digital soil mapping for the support of delineation of Areas Facing Natural Constraints defined by common European biophysical criteria

    Science.gov (United States)

    Pásztor, László; Bakacsi, Zsófia; Laborczi, Annamária; Takács, Katalin; Szatmári, Gábor; Tóth, Tibor; Szabó, József

    2016-04-01

    One of the main objectives of the EU's Common Agricultural Policy is to encourage maintaining agricultural production in Areas Facing Natural Constraints (ANC) in order to sustain agricultural production and use natural resources, in such a way to secure both stable production and income to farmers and to protect the environment. ANC assignment has both ecological and severe economical aspects. Recently the delimitation of ANCs is suggested to be carried out by using common biophysical diagnostic criteria on low soil productivity and poor climate conditions all over Europe. The criterion system was elaborated and has been repeatedly upgraded by JRC. The operational implementation is under member state competence. This process requires application of available soil databases and proper thematic and spatial inference methods. In our paper we present the inferences applied for the latest identification and delineation of areas with low soil productivity in Hungary according to JRC biophysical criteria related to soil: limited soil drainage, texture and stoniness (coarse texture, heavy clay, vertic properties), shallow rooting depth, chemical properties (salinity, sodicity, low pH). The compilation of target specific maps were based on the available legacy and recently collected data. In the present work three different data sources were used. The most relevant available data were queried from the datasets for each mapped criterion for either direct application or for the compilation a suitable, synthetic (non-measured) parameter. In some cases the values of the target variable originated from only one, in other cases from more databases. The reference dataset used in the mapping process was set up after substantial statistical analysis and filtering. It consisted of the values of the target variable attributed to the finally selected georeferenced locations. For spatial inference regression kriging was applied. Accuracy assessment was carried out by Leave One Out

  18. Calculation of Pareto-optimal solutions to multiple-objective problems using threshold-of-acceptability constraints

    Science.gov (United States)

    Giesy, D. P.

    1978-01-01

    A technique is presented for the calculation of Pareto-optimal solutions to a multiple-objective constrained optimization problem by solving a series of single-objective problems. Threshold-of-acceptability constraints are placed on the objective functions at each stage to both limit the area of search and to mathematically guarantee convergence to a Pareto optimum.

  19. Multiple-use Management of Irrigation Systems: Technical Constraints and Challenges

    Science.gov (United States)

    Gowing, J.; Li, Q.; Mayilswami, C.; Gunawardhana, K.

    It is now widely recognised that many irrigation systems, originally planned only for irrigation supply, are de facto multiple-use systems. However, the importance of non- irrigation uses (such as bathing, laundry, livestock watering and fishing), to the liveli- hoods of the rural poor has generally been ignored. This has significant implications for irrigation engineers, water resources managers and other decision-makers. An im- proved understanding of competition and complementarity between these uses and irrigation demands is essential for effective multiple-use management of irrigation systems.This paper presents a study of multiple-use management, where the focus is on integrating aquaculture within irrigation systems with and without secondary storage. The Lower Bhavani scheme in South India and Mahaweli System H in Sri- Lanka were selected as representative smallholder irrigation schemes: - The Lower Bhavani scheme comprises a 200km contour canal serving a command area of 78,500ha. Apart from the main dam, there are no storage structures within the irriga- tion system. - Mahaweli System H comprises a command area of 43,000ha served by three main canals. The feature of particular interest in this scheme is the large number of secondary storage structures (known locally as tanks), which are in- tegrated within the canal network. It is apparent from these two sites and from studies elsewhere that non-irrigation uses are important to the livelihoods of the local peo- ple, but these uses are largely opportunistic. The failure to give explicit recognition to non-irrigation uses has important implications for assessments of economic per- formance and water productivity of irrigation systems. However, any attempt to give proper recognition to these alternative uses also has implication for irrigation project management. This paper describes a detailed study of water management in the two irrigation systems. The method of investigation involves in-depth studies in

  20. Adult attachment, hostile conflict, and relationship adjustment among couples facing multiple sclerosis.

    Science.gov (United States)

    Crangle, Cassandra J; Hart, Tae L

    2017-07-12

    Couples facing multiple sclerosis (MS) report significantly elevated rates of relationship distress, yet the effects of attachment have never been examined in this population. We examined whether hostile conflict mediated the dyadic effects of attachment on relationship adjustment in couples facing MS and whether these associations were moderated by gender or role. We also explored whether dyadic adjustment mediated the relationship between attachment and hostile conflict. The study was cross-sectional and included 103 couples in which one partner had been diagnosed with MS. Participants completed the Experiences in Close Relationships-Revised, Dyadic Adjustment Scale, and Aversive Interactions Scale, as well as demographic variables. We used the actor-partner interdependence model for data analysis. There were significant actor and partner effects of greater anxious attachment and worse dyadic adjustment. Actor and partner effects of anxious attachment were significantly mediated by greater hostile conflict. Gender significantly moderated the effects between avoidant attachment and dyadic adjustment. The actor effect was significant for males and females; the partner effect was only significant for females. The actor effect for females but not males was significantly mediated by greater hostile conflict. Role was not a significant moderator. Exploratory analyses also showed that dyadic adjustment mediated the relationship between anxious and avoidant attachment and hostile conflict. Findings highlight the important effects of attachment on relationship adjustment in MS couples. Both hostile conflict and dyadic adjustment appear to be mechanisms through which insecure attachment has a detrimental effect. Statement of contribution What is already known on this subject? Despite higher-than-normal rates of marital distress and separation/divorce, the effects of attachment on relationship adjustment among couples facing multiple sclerosis have never been examined

  1. Development and validation of risk profiles of West African rural communities facing multiple natural hazards.

    Science.gov (United States)

    Asare-Kyei, Daniel; Renaud, Fabrice G; Kloos, Julia; Walz, Yvonne; Rhyner, Jakob

    2017-01-01

    West Africa has been described as a hotspot of climate change. The reliance on rain-fed agriculture by over 65% of the population means that vulnerability to climatic hazards such as droughts, rainstorms and floods will continue. Yet, the vulnerability and risk levels faced by different rural social-ecological systems (SES) affected by multiple hazards are poorly understood. To fill this gap, this study quantifies risk and vulnerability of rural communities to drought and floods. Risk is assessed using an indicator-based approach. A stepwise methodology is followed that combines participatory approaches with statistical, remote sensing and Geographic Information System techniques to develop community level vulnerability indices in three watersheds (Dano, Burkina Faso; Dassari, Benin; Vea, Ghana). The results show varying levels of risk profiles across the three watersheds. Statistically significant high levels of mean risk in the Dano area of Burkina Faso are found whilst communities in the Dassari area of Benin show low mean risk. The high risk in the Dano area results from, among other factors, underlying high exposure to droughts and rainstorms, longer dry season duration, low caloric intake per capita, and poor local institutions. The study introduces the concept of community impact score (CIS) to validate the indicator-based risk and vulnerability modelling. The CIS measures the cumulative impact of the occurrence of multiple hazards over five years. 65.3% of the variance in observed impact of hazards/CIS was explained by the risk models and communities with high simulated disaster risk generally follow areas with high observed disaster impacts. Results from this study will help disaster managers to better understand disaster risk and develop appropriate, inclusive and well integrated mitigation and adaptation plans at the local level. It fulfills the increasing need to balance global/regional assessments with community level assessments where major decisions

  2. Using Multiple Sources of Information for Constraint-Based Morphological Disambiguation

    CERN Document Server

    Tur, G

    1999-01-01

    This thesis presents a constraint-based morphological disambiguation approach that is applicable to languages with complex morphology--specifically agglutinative languages with productive inflectional and derivational morphological phenomena. For morphologically complex languages like Turkish, automatic morphological disambiguation involves selecting for each token morphological parse(s), with the right set of inflectional and derivational markers. Our system combines corpus independent hand-crafted constraint rules, constraint rules that are learned via unsupervised learning from a training corpus, and additional statistical information obtained from the corpus to be morphologically disambiguated. The hand-crafted rules are linguistically motivated and tuned to improve precision without sacrificing recall. In certain respects, our approach has been motivated by Brill's recent work, but with the observation that his transformational approach is not directly applicable to languages like Turkish. Our approach a...

  3. Dual-target cost in visual search for multiple unfamiliar faces.

    Science.gov (United States)

    Mestry, Natalie; Menneer, Tamaryn; Cave, Kyle R; Godwin, Hayward J; Donnelly, Nick

    2017-08-01

    The efficiency of visual search for one (single-target) and either of two (dual-target) unfamiliar faces was explored to understand the manifestations of capacity and guidance limitations in face search. The visual similarity of distractor faces to target faces was manipulated using morphing (Experiments 1 and 2) and multidimensional scaling (Experiment 3). A dual-target cost was found in all experiments, evidenced by slower and less accurate search in dual- than single-target conditions. The dual-target cost was unequal across the targets, with performance being maintained on one target and reduced on the other, which we label "preferred" and "non-preferred" respectively. We calculated the capacity for each target face and show reduced capacity for representing the non-preferred target face. However, results show that the capacity for the non-preferred target can be increased when the dual-target condition is conducted after participants complete the single-target conditions. Analyses of eye movements revealed evidence for weak guidance of fixations in single-target search, and when searching for the preferred target in dual-target search. Overall, the experiments show dual-target search for faces is capacity- and guidance-limited, leading to superior search for 1 face over the other in dual-target search. However, learning faces individually may improve capacity with the second face. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  4. Paleoarchean sulfur cycling : Multiple sulfur isotope constraints from the Barberton Greenstone Belt, South Africa

    NARCIS (Netherlands)

    Montinaro, Alice; Strauss, Harald; Mason, Paul R D; Roerdink, Desiree; Münker, Carsten; Schwarz-Schampera, Ulrich; Arndt, Nicholas T.; Farquhar, James; Beukes, Nicolas J.; Gutzmer, Jens; Peters, Marc

    2015-01-01

    Mass-dependent and mass-independent sulfur isotope fractionation archived in volcanic and sedimentary rocks from the Barberton Greenstone Belt (3550-3215. Ma), South Africa, provide constraints for sulfur cycling on the early Earth. Four different sample suites were studied: komatiites and tholeiite

  5. Face Super-resolution With Non-negative Featrue Basis Constraint%非负特征基约束的人脸超分辨率

    Institute of Scientific and Technical Information of China (English)

    兰诚栋; 胡瑞敏; 韩镇; 卢涛

    2011-01-01

    Principal Component Analysis (PC A) is commonly used for human face images representation in face super-resolution. But the features extracted by PCA are holistic and difficult to have semantic interpretation. In order to synthesize a better super-resolution face image with the results of the face images representation, we propose face a super-resolution algorithm with non-negative featrue basis constraint The algorithm uses the NMF to obtain non-negative featrue basis of face sample images, and the target image is regularized by Markov random fields, with maximum a posteriori probability approach. Finally, the steepest descent method is used to optimize non-negative featrue basis coefficient of high-resolution image. Experimental results show that, in the subjective and objective quality, the face super-resolution algorithm with non-negative feature basis constrait performs better than PCA-based algorithms.%主成分分析(PCA)是人脸超分辨率申常用的人脸图像表达方法,但是PCA方法的特征是整体的且难以语义解释.为了使表达的结果更好地用于合成超分辨率人脸图像,提出一种非负特征基约束的人脸超分辨率算法.该算法利用非负矩阵分解(NMF)获取样本人脸图像的非负特征基,结合最大后验概率的方法,对目标图像进行马尔可夫随机场正则约束,最速下降法优化得到高分辨率人脸图像的非负特征基系数.实验结果表明,在主客观质量上,非负特征基约束的人脸超分辨率算法的性能胜过基于PCA的算法.

  6. Distinct representations of configural and part information across multiple face- selective regions of the human brain

    Directory of Open Access Journals (Sweden)

    Golijeh eGolarai

    2015-11-01

    Full Text Available Several regions of the human brain respond more strongly to faces than to other visual stimuli, such as regions in the amygdala (AMG, superior temporal sulcus (STS, and the fusiform face area (FFA. It is unclear if these brain regions are similar in representing the configuration or natural appearance of face parts. We used functional magnetic resonance imaging of healthy adults who viewed natural or schematic faces with internal parts that were either normally configured or randomly rearranged. Response amplitudes were reduced in the AMG and STS when subjects viewed stimuli whose configuration of parts were digitally rearranged, suggesting representation of the 1st order configuration of face parts. In contrast, response amplitudes in the FFA showed little modulation whether face parts were rearranged or if the natural face parts were replaced with lines. Instead, FFA responses were reduced only when both configural and part information were reduced, revealing an interaction between these factors, suggesting distinct representation of 1st order face configuration and parts in the AMG and STS vs. the FFA.

  7. Gruppenleistungen beim Review von Multiple-Choice-Fragen - Ein Vergleich von face-to-face und virtuellen Gruppen mit und ohne Moderation [Review of multiple-choice-questions and group performance - A comparison of face-to-face and virtual groups with and without facilitation

    Directory of Open Access Journals (Sweden)

    Schüttpelz-Brauns, Katrin

    2010-11-01

    Full Text Available [english] Background: Multiple choice questions (MCQs are often used in exams of medical education and need careful quality management for example by the application of review committees. This study investigates whether groups communicating virtually by email are similar to face-to-face groups concerning their review process performance and whether a facilitator has positive effects.Methods: 16 small groups of students were examined, which had to evaluate and correct MCQs under four different conditions. In the second part of the investigation the changed questions were given to a new random sample for the judgement of the item quality.Results: There was no significant influence of the variables “form of review committee” and “facilitation”. However, face-to-face and virtual groups clearly differed in the required treatment times. The test condition “face to face without facilitation” was generally valued most positively concerning taking over responsibility, approach to work, sense of well-being, motivation and concentration on the task.Discussion: Face-to-face and virtual groups are equally effective in the review of MCQs but differ concerning their efficiency. The application of electronic review seems to be possible but is hardly recommendable because of the long process time and technical problems.[german] Einleitung: Multiple-Choice-Fragen (MCF werden in vielen Prüfungen der medizinischen Ausbildung verwendet und bedürfen aus diesem Grund einer sorgfältigen Qualitätssicherung, beispielsweise durch den Einsatz von Review-Komitees. Anhand der vorliegenden empirischen Studie soll erforscht werden, ob virtuell per E-Mail kommunizierende Review-Komitees vergleichbar sind mit face-to-face Review-Komitees hinsichtlich ihrer Leistung beim Review-Prozess und ob sich Moderation positiv auswirkt.Methodik: 16 Kleingruppen von Psychologie-Studenten hatten die Aufgabe unter vier verschiedenen Versuchsbedingungen MCF zu bewerten und zu

  8. A UNIVERSAL APPROACH FOR CONTINUOUS OR DISCRETE NONLINEAR PROGRAMMINGS WITH MULTIPLE VARIABLES AND CONSTRAINTS

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A universal numerical approach for nonlinear mathematic programming problems is presented with an application of ratios of first-order differentials/differences of objective functions to constraint functions with respect to design variables. This approach can be efficiently used to solve continuous and, in particular, discrete programmings with arbitrary design variables and constraints. As a search method, this approach requires only computations of the functions and their partial derivatives or differences with respect to design variables, rather than any solution of mathematic equations. The present approach has been applied on many numerical examples as well as on some classical operational problems such as one-dimensional and two-dimensional knap-sack problems, one-dimensional and two-dimensional resource-distribution problems, problems of working reliability of composite systems and loading problems of machine, and more efficient and reliable solutions are obtained than traditional methods. The present approach can be used without limitation of modeling scales of the problem. Optimum solutions can be guaranteed as long as the objective function,constraint functions and their first-order derivatives/differences exist in the feasible domain or feasible set. There are no failures of convergence and instability when this approach is adopted.

  9. More than just a pretty face and a hot body: multiple cues in mate-choice.

    Science.gov (United States)

    Jonason, Peter K; Raulston, Tara; Rotolo, Ashley

    2012-01-01

    Mate preferences have been well studied in social and evolutionary psychology. In two studies (N = 490), using two different measurement techniques, we examined mate preferences for the body and the face in the context of other traits. Results replicated prior research on mate preferences across the sex of the participant and mating duration but clarified the nature of preferences for physical attractiveness. Generally, physical attractiveness was a necessity in short-term mating and for men and traits like kindness were a necessity in long-term mating and for women. Men wanted a short-term mate who had a good body, likely because that body advertises fertility whereas both sexes wanted a mate with a nice face for a long-term mate, which is likely because the face is a cue based on structural properties related to health. Sex and mating-duration differences on preferences for attractive faces and bodies were robust to differences in measurement technique.

  10. Efficient video panoramic image stitching based on an improved selection of Harris corners and a multiple-constraint corner matching.

    Directory of Open Access Journals (Sweden)

    Minchen Zhu

    Full Text Available Video panoramic image stitching is extremely time-consuming among other challenges. We present a new algorithm: (i Improved, self-adaptive selection of Harris corners. The successful stitching relies heavily on the accuracy of corner selection. We fragment each image into numerous regions and select corners within each region according to the normalized variance of region grayscales. Such a selection is self-adaptive and guarantees that corners are distributed proportional to region texture information. The possible clustering of corners is also avoided. (ii Multiple-constraint corner matching. The traditional Random Sample Consensus (RANSAC algorithm is inefficient, especially when handling a large number of images with similar features. We filter out many inappropriate corners according to their position information, and then generate candidate matching pairs based on grayscales of adjacent regions around corners. Finally we apply multiple constraints on every two pairs to remove incorrectly matched pairs. By a significantly reduced number of iterations needed in RANSAC, the stitching can be performed in a much more efficient manner. Experiments demonstrate that (i our corner matching is four times faster than normalized cross-correlation function (NCC rough match in RANSAC and (ii generated panoramas feature a smooth transition in overlapping image areas and satisfy real-time human visual requirements.

  11. Cooperatively surrounding control for multiple Euler-Lagrange systems subjected to uncertain dynamics and input constraints

    Science.gov (United States)

    Chen, Liang-Ming; Lv, Yue-Yong; Li, Chuan-Jiang; Ma, Guang-Fu

    2016-12-01

    In this paper, we investigate cooperatively surrounding control (CSC) of multi-agent systems modeled by Euler-Lagrange (EL) equations under a directed graph. With the consideration of the uncertain dynamics in an EL system, a backstepping CSC algorithm combined with neural-networks is proposed first such that the agents can move cooperatively to surround the stationary target. Then, a command filtered backstepping CSC algorithm is further proposed to deal with the constraints on control input and the absence of neighbors’ velocity information. Numerical examples of eight satellites surrounding one space target illustrate the effectiveness of the theoretical results. Project supported by the National Basic Research Program of China (Grant No. 2012CB720000) and the National Natural Science Foundation of China (Grant Nos. 61304005 and 61403103).

  12. DEWA: A Multiaspect Approach for Multiple Face Detection in Complex Scene Digital Image

    Directory of Open Access Journals (Sweden)

    Setiawan Hadi

    2013-09-01

    Full Text Available A new approach for detecting faces in a digital image with unconstrained background has been developed. The approach is composed of three phases: segmentation phase, filtering phase and localization phase. In the segmentation phase, we utilized both training and non-training methods, which are implemented in user selectable color space. In the filtering phase, Minkowski addition-based objects removal has been used for image cleaning. In the last phase, an image processing method and a data mining method are employed for grouping and localizing objects, combined with geometric-based image analysis. Several experiments have been conducted using our special face database that consists of simple objects and complex objects. The experiment results demonstrated that the detection accuracy is around 90% and the detection speed is less than 1 second in average.

  13. DEWA: A Multiaspect Approach for Multiple Face Detection in Complex Scene Digital Image

    Directory of Open Access Journals (Sweden)

    Setiawan Hadi

    2007-05-01

    Full Text Available A new approach for detecting faces in a digital image with unconstrained background has been developed. The approach is composed of three phases: segmentation phase, filtering phase and localization phase. In the segmentation phase, we utilized both training and non-training methods, which are implemented in user selectable color space. In the filtering phase, Minkowski addition-based objects removal has been used for image cleaning. In the last phase, an image processing method and a data mining method are employed for grouping and localizing objects, combined with geometric-based image analysis. Several experiments have been conducted using our special face database that consists of simple objects and complex objects. The experiment results demonstrated that the detection accuracy is around 90% and the detection speed is less than 1 second in average.

  14. a Robust Method for Stereo Visual Odometry Based on Multiple Euclidean Distance Constraint and Ransac Algorithm

    Science.gov (United States)

    Zhou, Q.; Tong, X.; Liu, S.; Lu, X.; Liu, S.; Chen, P.; Jin, Y.; Xie, H.

    2017-07-01

    Visual Odometry (VO) is a critical component for planetary robot navigation and safety. It estimates the ego-motion using stereo images frame by frame. Feature points extraction and matching is one of the key steps for robotic motion estimation which largely influences the precision and robustness. In this work, we choose the Oriented FAST and Rotated BRIEF (ORB) features by considering both accuracy and speed issues. For more robustness in challenging environment e.g., rough terrain or planetary surface, this paper presents a robust outliers elimination method based on Euclidean Distance Constraint (EDC) and Random Sample Consensus (RANSAC) algorithm. In the matching process, a set of ORB feature points are extracted from the current left and right synchronous images and the Brute Force (BF) matcher is used to find the correspondences between the two images for the Space Intersection. Then the EDC and RANSAC algorithms are carried out to eliminate mismatches whose distances are beyond a predefined threshold. Similarly, when the left image of the next time matches the feature points with the current left images, the EDC and RANSAC are iteratively performed. After the above mentioned, there are exceptional remaining mismatched points in some cases, for which the third time RANSAC is applied to eliminate the effects of those outliers in the estimation of the ego-motion parameters (Interior Orientation and Exterior Orientation). The proposed approach has been tested on a real-world vehicle dataset and the result benefits from its high robustness.

  15. Temperature Histories of Structural Steel Laser and Hybrid Laser-GMA Welds Calculated Using Multiple Constraints

    Science.gov (United States)

    2015-12-10

    Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/6390--15-9665 Temperature Histories of Structural Steel Laser and Hybrid Laser-GMA Welds...NUMBER OF PAGES 17. LIMITATION OF ABSTRACT Temperature Histories of Structural Steel Laser and Hybrid Laser-GMA Welds Calculated Using Multiple...202) 767-2601 Inverse thermal analyses of structural steel deep-penetration welds are presented. These analyses employ a methodology that is in terms of

  16. Multiple Constraints Based Robust Matching of Poor-Texture Close-Range Images for Monitoring a Simulated Landslide

    Directory of Open Access Journals (Sweden)

    Gang Qiao

    2016-05-01

    Full Text Available Landslides are one of the most destructive geo-hazards that can bring about great threats to both human lives and infrastructures. Landslide monitoring has been always a research hotspot. In particular, landslide simulation experimentation is an effective tool in landslide research to obtain critical parameters that help understand the mechanism and evaluate the triggering and controlling factors of slope failure. Compared with other traditional geotechnical monitoring approaches, the close-range photogrammetry technique shows potential in tracking and recording the 3D surface deformation and failure processes. In such cases, image matching usually plays a critical role in stereo image processing for the 3D geometric reconstruction. However, the complex imaging conditions such as rainfall, mass movement, illumination, and ponding will reduce the texture quality of the stereo images, bringing about difficulties in the image matching process and resulting in very sparse matches. To address this problem, this paper presents a multiple-constraints based robust image matching approach for poor-texture close-range images particularly useful in monitoring a simulated landslide. The Scale Invariant Feature Transform (SIFT algorithm was first applied to the stereo images for generation of scale-invariate feature points, followed by a two-step matching process: feature-based image matching and area-based image matching. In the first feature-based matching step, the triangulation process was performed based on the SIFT matches filtered by the Fundamental Matrix (FM and a robust checking procedure, to serve as the basic constraints for feature-based iterated matching of all the non-matched SIFT-derived feature points inside each triangle. In the following area-based image-matching step, the corresponding points of the non-matched features in each triangle of the master image were predicted in the homologous triangle of the searching image by using geometric

  17. Multiple minor mergers: formation of elliptical galaxies and constraints for the growth of spiral disks

    CERN Document Server

    Bournaud, Frederic; Combes, Francoise

    2007-01-01

    Multiple, sequential mergers are unavoidable in the hierarchical build-up picture of galaxies, in particular for the minor mergers that are frequent and highly likely to have occured several times for most present-day galaxies. However the effect of repeated minor mergers on galactic structure and evolution has not been studied systematically so far. In this paper, we present a numerical study of multiple, subsequent, minor galaxy mergers, with various mass ratios ranging from 4:1 to 50:1. The N-body simulations include gas dynamics and star formation. We study the morphological and kinematical properties of the remnants, and show that several so-called "minor" mergers can lead to the formation of elliptical-like galaxies, that have global morphological and kinematical properties similar to that observed in real elliptical galaxies. The properties of these systems are compared with that of elliptical galaxies produced by the standard scenario of one single major merger. We thus show that repeated minor merger...

  18. The κ Andromedae system: new constraints on the companion mass, system age, and further multiplicity

    Energy Technology Data Exchange (ETDEWEB)

    Hinkley, Sasha; David, Trevor; Hillenbrand, Lynne A. [Department of Astronomy, California Institute of Technology, 1200 East California Boulevard, MC 249-17, Pasadena, CA 91125 (United States); Pueyo, Laurent [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Faherty, Jacqueline K. [Department of Astronomy, Universidad de Chile Cerro Calan, Las Condes (Chile); Oppenheimer, Ben R.; Brenner, Douglas; Veicht, Aaron; Nilsson, Ricky [Astrophysics Department, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024 (United States); Mamajek, Eric E. [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627-0171 (United States); Kraus, Adam L. [Harvard-Smithsonian CfA, 60 Garden Street, Cambridge, MA 02140 (United States); Rice, Emily L. [Department of Engineering Science and Physics, College of Staten Island, City University of New York, Staten Island, NY 10314 (United States); Ireland, Michael J. [Department of Physics and Astronomy, Macquarie University, Sydney, NSW 2109 (Australia); Vasisht, Gautam; Cady, Eric; Roberts, Jennifer E. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Zimmerman, Neil [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Parry, Ian R. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Beichman, Charles [NASA Exoplanet Science Institute, California Institute of Technology, Pasadena, CA 91125 (United States); Dekany, Richard [Caltech Optical Observatories, California Institute of Technology, Pasadena, CA 91125 (United States); and others

    2013-12-20

    κ Andromedae is a B9IVn star at 52 pc for which a faint substellar companion separated by 55 ± 2 AU was recently announced. In this work, we present the first spectrum of the companion, 'κ And B,' using the Project 1640 high-contrast imaging platform. Comparison of our low-resolution YJH-band spectra to empirical brown dwarf spectra suggests an early-L spectral type. Fitting synthetic spectra from PHOENIX model atmospheres to our observed spectrum allows us to constrain the effective temperature to ∼2000 K as well as place constraints on the companion surface gravity. Further, we use previously reported log(g) and T {sub eff} measurements of the host star to argue that the κ And system has an isochronal age of 220 ± 100 Myr, older than the 30 Myr age reported previously. This interpretation of an older age is corroborated by the photometric properties of κ And B, which appear to be marginally inconsistent with other 10-100 Myr low-gravity L-dwarfs for the spectral type range we derive. In addition, we use Keck aperture masking interferometry combined with published radial velocity measurements to rule out the existence of any tight stellar companions to κ And A that might be responsible for the system's overluminosity. Further, we show that luminosity enhancements due to a nearly 'pole-on' viewing angle coupled with extremely rapid rotation is unlikely. κ And A is thus consistent with its slightly evolved luminosity class (IV), and we propose here that κ And, with a revised age of 220 ± 100 Myr, is an interloper to the 30 Myr Columba association with which it was previously associated. The photometric and spectroscopic evidence for κ And B combined with our reassessment of the system age implies a substellar companion mass of 50{sub −13}{sup +16} M {sub Jup}, consistent with a brown dwarf rather than a planetary-mass companion.

  19. Distributed Cooperative Control of Multiple Nonlinear Systems with Nonholonomic Constraints and Uncertainty

    Science.gov (United States)

    2015-04-04

    trajectory xd = [x1d, . . . , xnd] ⊤ which is generated by ẋ1d = v1d (12.4) ẋ2d = v2d (12.5) ẋid = v1dxi−1,d, 3 ≤ i ≤ n (12.6) where v1d and v2d are...defined as follows. Tracking Control of Multiple Chained Systems: For a group of m systems in (12.1)-(12.3), it is given a desired trajectory xd , the...x∗j − xd ) = 0, 1 ≤ j ≤ m, (12.7) where x∗j = [x1j , . . . , xnj ] ⊤. It is assumed that the uncertain terms in (12.1)-(12.3) satisfy the following

  20. Facing Title V permit constraints

    Energy Technology Data Exchange (ETDEWEB)

    Patankar, U.M. [JACA Corp., Fort Washington, PA (United States)

    1995-06-01

    The new Title V operating permit requirement under state regulations pursuant to the 1990 Clean Air Act Amendments will cover every emission source at a facility. These rules will significantly affect an operation by setting minimum compliance requirements, mandating periodic compliance certification, prescribing complex monitoring, record keeping and reporting procedures and making state and EPA approval of routine operational changes necessary through a permit amendment. The main concern with Title V is its effect on the operational flexibility of a facility, and individual emission sources within that facility. Unless properly addressed in a permit document, the term operational flexibility, so freely used by regulators in the context of the Title V program, can turn into a misnomer and the ability to operate as before may be significantly compromised under Title V. True operational flexibility is essential for businesses to respond to real changes in the marketplace. In the age of automation, just-in-time inventories and increased competition, flexibility to operate can mean the difference between growth and stagnation.

  1. Effect of phone call versus face-to-face follow-up on recurrent suicide attempts prevention in individuals with a history of multiple suicide attempts

    Science.gov (United States)

    Mousavi, Seyed Ghafur; Amini, Mohsen; Mahaki, Behzad; Bagherian-Sararoudi, Reza

    2016-01-01

    Background: To evaluate the efficacy of different ways of communications on prevention of suicidal reattempt, we compared the efficacy of phone call versus face-to-face follow-up in patients with previous attempt. Materials and Methods: In a randomized controlled clinical trial, 55 suicide reattempters who were admitted to the poisoning emergency were divided into phone call (29 patients) and face-to-face (26 patients) groups randomly. They were followed at 8 occasions: 2nd and 4th weeks, and the 2nd, 3rd, 4th, 5th, 6th, and 8th months. The suicidal reattempt, suicidal thought, hope, and interest of the patients were assessed on each occasion, and the patients were guided to visit by a therapist, if needed. The findings were analyzed by Mann–Whitney, Chi-square, Cochran, Friedman, and independent t-tests using SPSS 20. Results: The status of “hope” and “interest” improved in both groups, but it showed more significant difference in the face-to-face group. Suicidal thoughts in both groups decreased over time, and this was more significant in the face-to-face group. However, we did not found any significant difference in the frequency of the suicidal reattempts between two groups. Conclusion: Face-to-face versus phone call follow-up of suicide attempters can significantly alleviate suicidal thoughts and improve hopes and interests. PMID:28028524

  2. LITHO1.0 - An Updated Crust and Lithospheric Model of the Earth Developed Using Multiple Data Constraints

    Science.gov (United States)

    Pasyanos, M. E.; Masters, G.; Laske, G.; Ma, Z.

    2012-12-01

    Models such as CRUST2.0 (Bassin et al., 2000) have proven very useful to many seismic studies on regional, continental, and global scales. We have developed an updated, higher resolution model called LITHO1.0 that extends deeper to include the lithospheric lid, and includes mantle anisotropy, potentially making it more useful for a wider variety of applications. The model is evolving away from the crustal types strongly used in CRUST5.1 (Mooney et al., 1998) to a more data-driven model. This is accomplished by performing a targeted grid search with multiple data inputs. We seek to find the most plausible model which is able to fit multiple constraints, including updated sediment and crustal thickness models, upper mantle velocities derived from travel times, and surface wave dispersion. The latter comes from a new, very large, global surface wave dataset built using a new, efficient measurement technique that employs cluster analysis (Ma et al., 2012), and includes the group and phase velocities of both Love and Rayleigh waves. We will discuss datasets and methodology, highlight significant features of the model, and provide detailed information on the availability of the model in various formats.

  3. Tools to support interpreting multiple regression in the face of multicollinearity.

    Science.gov (United States)

    Kraha, Amanda; Turner, Heather; Nimon, Kim; Zientek, Linda Reichwein; Henson, Robin K

    2012-01-01

    While multicollinearity may increase the difficulty of interpreting multiple regression (MR) results, it should not cause undue problems for the knowledgeable researcher. In the current paper, we argue that rather than using one technique to investigate regression results, researchers should consider multiple indices to understand the contributions that predictors make not only to a regression model, but to each other as well. Some of the techniques to interpret MR effects include, but are not limited to, correlation coefficients, beta weights, structure coefficients, all possible subsets regression, commonality coefficients, dominance weights, and relative importance weights. This article will review a set of techniques to interpret MR effects, identify the elements of the data on which the methods focus, and identify statistical software to support such analyses.

  4. Carbon balance assessment of a natural steppe of southern Siberia by multiple constraint approach

    Directory of Open Access Journals (Sweden)

    L. Belelli Marchesini

    2007-08-01

    Full Text Available Steppe ecosystems represent an interesting case in which the assessment of carbon balance may be performed through a cross validation of the eddy covariance measurements against ecological inventory estimates of carbon exchanges (Ehman et al., 2002; Curtis et al., 2002.

    Indeed, the widespread presence of ideal conditions for the applicability of the eddy covariance technique, as vast and homogeneous grass vegetation cover over flat terrains (Baldocchi, 2003, make steppes a suitable ground to ensure a constrain to flux estimates with independent methodological approaches.

    We report about the analysis of the carbon cycle of a true steppe ecosystem in southern Siberia during the growing season of 2004 in the framework of the TCOS-Siberia project activities performed by continuous monitoring of CO2 fluxes at ecosystem scale by the eddy covariance method, fortnightly samplings of phytomass, and ingrowth cores extractions for NPP assessment, and weekly measurements of heterotrophic component of soil CO2 effluxes obtained by an experiment of root exclusion.

    The carbon balance of the monitored natural steppe was, according to micrometeorological measurements, a sink of carbon of 151.7±36.9 g C m−2, cumulated during the growing season from May to September. This result was in agreement with the independent estimate through ecological inventory which yielded a sink of 150.1 g C m−2 although this method was characterized by a large uncertainty (±130% considering the 95% confidence interval of the estimate. Uncertainties in belowground process estimates account for a large part of the error. Thus, in particular efforts to better quantify the dynamics of root biomass (growth and turnover have to be undertaken in order to reduce the uncertainties in the assessment of NPP. This assessment should be preferably based on the application of multiple methods, each one characterized by its

  5. Carbon Balance Assessment of a Natural Steppe of Southern Siberia by Multiple Constraint Approach

    Science.gov (United States)

    Belelli, L.; Papale, D.; Reichstein, M.; Vuichard, N.; Tchebakova, N.; Valentini, R.

    2007-12-01

    Steppe ecosystems represent an interesting case in which the assessment of carbon balance may be performed through a cross validation of the eddy covariance measurements against ecological inventory estimates of carbon exchanges (Ehman et al., 2002; Curtis et al., 2002). Indeed, the widespread presence of ideal conditions for the applicability of the eddy covariance technique, as vast and homogeneous grass vegetation cover over flat terrains (Baldocchi, 2003), make steppes a suitable ground to ensure a constrain to flux estimates with independent methodological approaches. We report about the analysis of the carbon cycle of a true steppe ecosystem in southern Siberia during the growing season of 2004 in the framework of the TCOS-Siberia project activities performed by continuous monitoring of CO2 fluxes at ecosystem scale by the eddy covariance method, fortnightly samplings of phytomass, and ingrowth cores extractions for NPP assessment, and weekly measurements of heterotrophic component of soil CO2 effluxes obtained by an experiment of root exclusion. The carbon balance of the monitored natural steppe was, according to micrometeorological measurements, a sink of carbon of 151.7±36.9 gC m-2, cumulated during the growing season from May to September. This result was in agreement with the independent estimate through ecological inventory which yielded a sink of 150.1 gC m-2 although this method was characterized by a large uncertainty \\(±130%\\) considering the 95% confidence interval of the estimate. Uncertainties in belowground process estimates account for a large part of the error. Thus, in particular efforts to better quantify the dynamics of root biomass (growth and turnover) have to be undertaken in order to reduce the uncertainties in the assessment of NPP. This assessment should be preferably based on the application of multiple methods, each one characterized by its own merits and flaws.

  6. Carbon balance assessment of a natural steppe of southern Siberia by multiple constraint approach

    Directory of Open Access Journals (Sweden)

    L. Belelli Marchesini

    2007-01-01

    Full Text Available Steppe ecosystems represent an interesting case in which the assessment of carbon balance may be performed through a cross validation of the eddy covariance measurements against ecological inventory estimates of carbon exchanges (Ehman, 2002; Curtis, 2002.

    Indeed, the widespread presence of ideal conditions for the applicability of the eddy covariance technique, as vast and homogeneous grass vegetation cover over flat terrains (Baldocchi, 2003, make steppes a suitable ground to ensure a constrain to flux estimates with independent methodological approaches.

    We report about the analysis of the carbon cycle of a true steppe ecosystem in southern Siberia during the growing season of 2004 in the framework of the TCOS-Siberia project activities performed by continuous monitoring of CO2 fluxes at ecosystem scale by the eddy covariance method, fortnightly samplings of phytomass, and ingrowth cores extractions for NPP assessment, and weekly measurements of heterotrophic component of soil CO2 effluxes obtained by an experiment of root exclusion.

    The carbon balance of the monitored natural steppe was, according to micrometeorological measurements, a sink of carbon of 151.7± 30.1 gC m−2, cumulated during the growing season from May to September. This result was in agreement with the independent estimate through ecological inventory which yielded a sink of 150.1 gC m−2 although this method was characterized by a large uncertainty (±130% considering the 95% confidence interval of the estimate. Uncertainties in belowground process estimates account for a large part of the error. Thus, in particular efforts to better quantify the dynamics of root biomass (growth and turnover have to be undertaken in order to reduce the uncertainties in the assessment of NPP. This assessment should be preferably based on the application of multiple methods, each one characterized by its own merits and

  7. One stone, two birds: managing multiple common warts on hands and face by local hyperthermia.

    Science.gov (United States)

    Hu, Lanting; Qi, Ruiqun; Hong, Yuxiao; Huo, Wei; Chen, Hong-Duo; Gao, Xing-Hua

    2015-01-01

    A man developed with multiple warts on his hands and the inner canthus of his left eye. We applied local hyperthermia on a single target lesion on his hand at a surface temperature of 44 °C for 30 minutes on Days 1, 2, 3, 17, and 18. All the lesions treated with or without heat cleared 8 weeks after the last treatment. Treatment of a target lesion resolved all other untreated lesions, a fact suggestive that local hyperthermia could induce activation of specific immunity against human papillomavirus on the lesional skin, which lead to resolution of all the warts. © 2014 Wiley Periodicals, Inc.

  8. Evaluation of a Multimedia Intervention for Children and Families Facing Multiple Military Deployments.

    Science.gov (United States)

    Flittner O'Grady, Allison; Thomaseo Burton, E; Chawla, Neelu; Topp, David; MacDermid Wadsworth, Shelley

    2016-02-01

    Repeated military deployments have been a common experience for many military families in the past 15 years. While there has been an increase in research and intervention focused on the effects on families of military deployments, much of this work has not focused specifically on the particular needs of young children. Talk, Listen, Connect: Multiple Deployments (TLC-II MD), a multimedia kit designed for home use, is among the first interventions directed toward young children. Created by Sesame Workshop and using popular Sesame Street characters, TLC-II MD was designed to support and equip families with young children with skills to address challenges associated with multiple deployments. This study utilized a randomized experimental design to evaluate the impact of TLC-II MD relative to a control condition using a Sesame Workshop multimedia kit not tailored to military families. Parents in both groups reported that children enjoyed the video overall and watched it repeatedly. Also in both groups, caregivers' depressive symptoms and children's aggressive behaviors declined significantly over time. Caregivers in the test group reported significantly larger increases in comfort discussing the deployment with their child and stronger perceptions that the DVD helped children to cope. Thus, the resilience-oriented materials were helpful to both groups, but those tailored to military families were significantly more likely to be perceived as helpful. Findings offer evidence regarding the ability of multimedia self-administered interventions to assist military families.

  9. The multiple faces of calcineurin signaling in Caenorhabditis elegans: Development, behaviour and aging

    Indian Academy of Sciences (India)

    Jin Il Lee; Sutapa Mukherjee; Kyoung–Hye Yoon; Meenakshi Dwivedi; Jaya Bandyopadhyay

    2013-06-01

    Calcineurin, a well-conserved protein phosphatase 2B (PP2B), is a Ca2+-calmodulin–dependent serine/threonine protein phosphatase that is known to be involved in a myriad of cellular processes and signal transduction pathways. The biological role of calcineurin has been extensively studied in diverse groups of organisms. Homologues of mammalian and Drosophila calcineurin subunits exist in the nematode, Caenorhabditis elegans. The C. elegans counterpart of the catalytic subunit, calcineurin A, cna-1/tax-6, and the regulatory subunit, calcineurin B, cnb-1, are known to express ubiquitously in multiple tissues including neurons. The characterization of C. elegans calcineurin mutants facilitates identification of its physiological functions and signaling pathways. Genetic interactions between cna-1/tax-6 and cnb-1 mutants with a number of mutants involved in several signaling pathways have exemplified the pivotal role of calcineurin in regulating nematode development, behaviour and lifespan (aging). The present review has been aimed to provide a succinct summary of the multiple functions of calcineurin in C. elegans relating to its development, fertility, proliferation, behaviour and lifespan. Analyses of cna-1/tax-6 and cnb-1 interacting proteins and regulators of the phosphatase in this fascinating worm model have an immense scope to identify potential drug targets in various parasitic nematodes, which cause many diseases inflicting huge economic loss; and also for many human diseases, particularly neurodegenerative and myocardial diseases.

  10. DAG tales: the multiple faces of diacylglycerol--stereochemistry, metabolism, and signaling.

    Science.gov (United States)

    Eichmann, Thomas Oliver; Lass, Achim

    2015-10-01

    The neutral lipids diacylglycerols (DAGs) are involved in a plethora of metabolic pathways. They function as components of cellular membranes, as building blocks for glycero(phospho)lipids, and as lipid second messengers. Considering their central role in multiple metabolic processes and signaling pathways, cellular DAG levels require a tight regulation to ensure a constant and controlled availability. Interestingly, DAG species are versatile in their chemical structure. Besides the different fatty acid species esterified to the glycerol backbone, DAGs can occur in three different stereo/regioisoforms, each with unique biological properties. Recent scientific advances have revealed that DAG metabolizing enzymes generate and distinguish different DAG isoforms, and that only one DAG isoform holds signaling properties. Herein, we review the current knowledge of DAG stereochemistry and their impact on cellular metabolism and signaling. Further, we describe intracellular DAG turnover and its stereochemistry in a 3-pool model to illustrate the spatial and stereochemical separation and hereby the diversity of cellular DAG metabolism.

  11. Dynamics of mechanical systems with multiple sliding contacts: new faces of Painlev\\'e's paradox

    CERN Document Server

    Várkonyi, Péter L

    2016-01-01

    We investigate the dynamics of finite degree-of-freedom, planar mechanical systems with multiple sliding, unilateral frictional point contacts. A complete classification of systems with 2 sliding contacts is given. The contact-mode based approach of rigid body mechanics is combined with linear stability analysis using a compliant contact model to determine the feasibility and the stability of every possible contact mode in each class. Special forms of non-stationary contact dynamics including "impact without collision" and "reverse chattering" are also investigated. Many types of solution inconsistency and the indeterminacy are identified and new phenomena related to Painlev\\'e"s non-existence and non-uniqueness paradoxes are discovered. Among others, we show that the non-existence paradox is not fully resolvable by considering impulsive contact forces. These results contribute to a growing body of evidence that rigid body mechanics cannot be developed into a complete and self-consistent theory in the presenc...

  12. The Multiple Faces of RAGE - Opportunities for Therapeutic Intervention in Aging and Chronic Disease

    Science.gov (United States)

    Ramasamy, Ravichandran; Shekhtman, Alexander; Schmidt, Ann Marie

    2016-01-01

    Introduction This review focuses on the multi-ligand receptor of the immunoglobulin superfamily, receptor for advanced glycation endproducts (RAGE). The accumulation of the multiple ligands of RAGE in cellular stress milieux links RAGE to the pathobiology of chronic disease and natural aging. Areas Covered In this review, we present a discussion on the ligands of RAGE and the implications of these ligand families in disease. We review the recent literature on the role of ligand-RAGE interaction in the consequences of natural aging; the macro- and microvascular complications of diabetes; obesity and insulin resistance; autoimmune disorders and chronic inflammation; tumors and Alzheimer’s disease. We discuss the mechanisms of RAGE signaling through its intracellular binding effector molecule, the formin DIAPH1. Physico-chemical evidence by which the RAGE cytoplasmic domain binds to the FH1 (formin homology 1) domain of DIAPH1, and the consequences, is also reviewed. Expert Opinion We discuss the modalities of RAGE antagonism currently in pre-clinical and clinical studies. Finally, we present the rationale behind potentially targeting the RAGE cytoplasmic domain-DIAPH1 interaction as a logical strategy for therapeutic intervention in the pathological settings of chronic diseases and aging in which RAGE ligands accumulate and signal. PMID:26558318

  13. Expression robust 3D face recognition via mesh-based histograms of multiple order surface differential quantities

    KAUST Repository

    Li, Huibin

    2011-09-01

    This paper presents a mesh-based approach for 3D face recognition using a novel local shape descriptor and a SIFT-like matching process. Both maximum and minimum curvatures estimated in the 3D Gaussian scale space are employed to detect salient points. To comprehensively characterize 3D facial surfaces and their variations, we calculate weighted statistical distributions of multiple order surface differential quantities, including histogram of mesh gradient (HoG), histogram of shape index (HoS) and histogram of gradient of shape index (HoGS) within a local neighborhood of each salient point. The subsequent matching step then robustly associates corresponding points of two facial surfaces, leading to much more matched points between different scans of a same person than the ones of different persons. Experimental results on the Bosphorus dataset highlight the effectiveness of the proposed method and its robustness to facial expression variations. © 2011 IEEE.

  14. Temperature Histories of Ti-6Al-4V Pulsed-Mode Laser Welds Calculated Using Multiple Constraints

    Science.gov (United States)

    2015-08-12

    the inclusion of volumetric constraint conditions whose two- dimensional projections are mappings onto transverse cross sections of experimentally...analysis procedure that provides for the inclusion of volumetric constraint conditions whose two- dimensional projections are mappings onto transverse...of solidification and transformation boundaries (WELD 1). . € C( ˆ x k ) € Δl € Δl 15 Fig. 3 Two- dimensional

  15. Notion of Control-Law Module and Modular Framework of Cooperative Transportation Using Multiple Nonholonomic Robotic Agents With Physical Rigid-Formation-Motion Constraints.

    Science.gov (United States)

    Li, Wei

    2016-05-01

    Consider cooperative manipulation and transportation of a rigid body by multiple two-wheeled nonholonomic robotic agents that attached to it, the agents are then physically constrained to maintain rigid-formation-motion (RFM); thus the system has two physical motion-constraints at two levels: 1) the nonholonomic constraint at the individual level and 2) the RFM constraint at the system level. First, we provide a novel notion: the encapsulation of a category of control with certain constraints for one motion-mode as a control-law module (CLM), any concrete control law with such constraints is called an instance of the CLM; here two CLMs are provided as the examples. Then we provide an RFM control framework by decomposing a feasible RFM configuration-path as a concatenation of partitions, with one type of CLMs for each partition; thus any instance for each partition can be designed separately and incorporated easily with the interchangeable property, which makes the framework modular, flexible, and adaptive, to satisfy different kinematics requirements. As a result, the transportation is achieved by RFM control of agents. Also, the RFM framework implies a valuable rigid-closure-method for accurate rigid body manipulation even when agents are not attached to the body.

  16. Distinct representations of configural and part information across multiple face-selective regions of the human brain

    OpenAIRE

    Golijeh eGolarai; Dara eGhahremani; Eberhardt, Jennifer L.; John D E Gabrieli

    2015-01-01

    Several regions of the human brain respond more strongly to faces than to other visual stimuli, such as regions in the amygdala (AMG), superior temporal sulcus (STS), and the fusiform face area (FFA). It is unclear if these brain regions are similar in representing the configuration or natural appearance of face parts. We used functional magnetic resonance imaging of healthy adults who viewed natural or schematic faces with internal parts that were either normally configured or randomly rearr...

  17. Upright or inverted, entire or exploded: right-hemispheric superiority in face recognition withstands multiple spatial manipulations

    Directory of Open Access Journals (Sweden)

    Giulia Prete

    2015-12-01

    Full Text Available Background. The ability to identify faces has been interpreted as a cerebral specialization based on the evolutionary importance of these social stimuli, and a number of studies have shown that this function is mainly lateralized in the right hemisphere. The aim of this study was to assess the right-hemispheric specialization in face recognition in unfamiliar circumstances.Methods. Using a divided visual field paradigm, we investigated hemispheric asymmetries in the matching of two subsequent faces, using two types of transformation hindering identity recognition, namely upside-down rotation and spatial “explosion” (female and male faces were fractured into parts so that their mutual spatial relations were left intact, as well as their combination.Results. We confirmed the right-hemispheric superiority in face processing. Moreover, we found a decrease of the identity recognition for more extreme “levels of explosion” and for faces presented upside-down (either as sample or target stimuli than for faces presented upright, as well as an advantage in the matching of female compared to male faces.Discussion. We conclude that the right-hemispheric superiority for face processing is not an epiphenomenon of our expertise, because we are not often exposed to inverted and “exploded” faces, but rather a robust hemispheric lateralization. We speculate that these results could be attributable to the prevalence of right-handedness in humans and/or to early biases in social interactions.

  18. Farmer responses to multiple stresses in the face of global change: Assessing five case studies to enhance adaptation

    Science.gov (United States)

    Nicholas, K. A.; Feola, G.; Lerner, A. M.; Jain, M.; Montefrio, M.

    2013-12-01

    The global challenge of sustaining agricultural livelihoods and yields in the face of growing populations and increasing climate change is the topic of intense research. The role of on-the-ground decision-making by individual farmers actually producing food, fuel, and fiber is often studied in individual cases to determine its environmental, economic, and social effects. However, there are few efforts to link across studies in a way that provides opportunities to better understand empirical farmer behavior, design effective policies, and be able to aggregate from case studies to a broader scale. Here we synthesize existing literature to identify four general factors affecting farmer decision-making: local technical and socio-cultural contexts; actors and institutions involved in decision-making; multiple stressors at broader scales; and the temporal gradient of decision-making. We use these factors to compare five cases that illustrate agricultural decision-making and its impacts: cotton and castor farming in Gujarat, India; swidden cultivation of upland rice in the Philippines; potato cultivation in Andean Colombia; winegrowing in Northern California; and maize production in peri-urban central Mexico. These cases span a geographic and economic range of production systems, but we find that we are able to make valid comparisons and draw lessons common across all cases by using the four factors as an organizing principle. We also find that our understanding of why farmers make the decisions they do changes if we neglect to examine even one of the four general factors guiding decision-making. This suggests that these four factors are important to understanding farmer decision-making, and can be used to guide the design and interpretation of future studies, as well as be the subject of further research in and of themselves to promote an agricultural system that is resilient to climate and other global environmental changes.

  19. Constraints on Multiple Object Tracking in Williams Syndrome: How Atypical Development Can Inform Theories of Visual Processing

    Science.gov (United States)

    Ferrara, Katrina; Hoffman, James E.; O'Hearn, Kirsten; Landau, Barbara

    2016-01-01

    The ability to track moving objects is a crucial skill for performance in everyday spatial tasks. The tracking mechanism depends on representation of moving items as coherent entities, which follow the spatiotemporal constraints of objects in the world. In the present experiment, participants tracked 1 to 4 targets in a display of 8 identical…

  20. Fast and Accurate 3D Face Recognition Using Registration to an Intrinsic Coordinate System and Fusion of Multiple Region classifiers

    NARCIS (Netherlands)

    Spreeuwers, Lieuwe Jan

    2011-01-01

    In this paper we present a new robust approach for 3D face registration to an intrinsic coordinate system of the face. The intrinsic coordinate system is defined by the vertical symmetry plane through the nose, the tip of the nose and the slope of the bridge of the nose. In addition, we propose a 3D

  1. Distinct representations of configural and part information across multiple face-selective regions of the human brain.

    Science.gov (United States)

    Golarai, Golijeh; Ghahremani, Dara G; Eberhardt, Jennifer L; Gabrieli, John D E

    2015-01-01

    Several regions of the human brain respond more strongly to faces than to other visual stimuli, such as regions in the amygdala (AMG), superior temporal sulcus (STS), and the fusiform face area (FFA). It is unclear if these brain regions are similar in representing the configuration or natural appearance of face parts. We used functional magnetic resonance imaging of healthy adults who viewed natural or schematic faces with internal parts that were either normally configured or randomly rearranged. Response amplitudes were reduced in the AMG and STS when subjects viewed stimuli whose configuration of parts were digitally rearranged, suggesting that these regions represent the 1st order configuration of face parts. In contrast, response amplitudes in the FFA showed little modulation whether face parts were rearranged or if the natural face parts were replaced with lines. Instead, FFA responses were reduced only when both configural and part information were reduced, revealing an interaction between these factors, suggesting distinct representation of 1st order face configuration and parts in the AMG and STS vs. the FFA.

  2. Evaluation of face-validity of multiple choice questions in special lessons of dentistry at Shahid Sadoughi University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    M. H Toodehzaiem

    2012-09-01

    Full Text Available Introduction: Evaluation is an important part of all educational activities and considering of these evaluations help us to improve all educational institutes . The aim of this study was evaluation of face validity of multiple choice questions in faculty of dentistry in second semester of 1385-1386 at Shahid Sadughi University of medical sciences. Methods : In this study, for evaluating of face validity, all of the multiple choice questions were examined with a check list which were considered and the percentage of face validity established . Then data were analyzed. Results : Introduction page, time of the exam and name of the professor(s were written in all of the exams. The independency of the questions and the lack of vague words in the question's stem were 100%. The percentage of each professor's contribution in the exam and the length of the choices for each question were 8.7% and 27.7% respectively. Conclusion : Face validity of the questions was 92-99.7%. According to this investigation it is concluded that some of the professors need to pass the question plan courses.

  3. The potential for SLM, facing human constraints, the case of the semi-arid agro-pastoral lands in the Atlantic plateaus, Morocco

    Science.gov (United States)

    Laouina, A.; Chaker, M.; Aderghal, M.; Machouri, N.; Alkarkouri, J.

    2012-04-01

    The agro-pastoral activity through its evolution, in the Atlantic plateaus of Morocco, led to unsuitable forms of resources use, which carried damage in the balance of water and the stability of land. It was thus necessary to start a revision of these practices and to set up improved forms of land use. The research made in the framework of the DESIRE project concerns the Sehoul commune, which presents a high rate of poverty and illiteracy, in spite of its location near Rabat, the capital of the country. Farming has as main objective to feed the livestock. The rain-based cereal cultivations, which still occupy more than 80% of the agricultural surface, reveals the stagnation of the techniques adopted and of the local knowledge. In collaboration with various stakeholders, technicians and farmers, the assessment with the WOCAT approach permitted to identify the main factors of constraints, responsible of the current spreading of land degradation mechanisms (forest clearing, shrubs cutting on the pastoral slopes, soil erosion, constitution of rills in the recently ploughed fields, incision of gullies and channels, mass movements on the banks of the deepest channels). These constraints derive from social evolution of the population during the last 60 years and mainly the rapid transformation of the rural structure of families to a new kind of farmers, more interested by what they can earn during their frequent movements to the city than by their own traditional agriculture. Due to the penetration of urban investment, direct overgrazing and indirect effect related to mismanagement of land for fodder production, operate massive damages to the vegetation cover and to the soil. It is why the SLM behavior, approaches and techniques have a very low rate of chance for success, without a deep change in term of land ownership, law constraints, agrarian structures, relations between the city and its vicinity, etc. Scenarios were built, based on various rates of land management

  4. 复杂约束条件下的UCAV多重任务分配%Multiple Task Assignment of Unmanned Combat Aerial Vehicles Under Complex Constraints

    Institute of Scientific and Technical Information of China (English)

    陈诚; 黄长强; 吴文超; 宋磊; 李望西; 谢化勇

    2012-01-01

    与单任务分配问题相比,无人作战飞机(UCAV)多重任务分配具有更复杂的约束条件.基于UCAV任务分配有向图给出了多重任务分配的一般框架,分析了任务分配的约束条件,提出了一种求解约束优化问题的改进遗传算法.其基本思想是对种群中的个体按两种方案评价,对可行解按目标函数值大小,对不可行解按约束违反程度进行评价,避免了罚函数法中的罚因子的选取难题.采用矩阵形式进行个体编码,按目标出现顺序映射任务类型,解决了多重任务的编码表示,并对武器类型向量实施绑定策略,简化了问题复杂性.设计了选择,交叉,变异等遗传操作算子,保证生成的新染色体不破坏编码时满足的约束条件.最后进行了仿真试验,结果表明提出的方法求解UCAV多重任务分配问题的可行性和有效性.%Multiple task assignment about Unmanned Combat Aerial Vehicles(UCAV) has more complex constraints compared to the single one. This paper presents a framework of UCAV task assignment based on the task assignment direction graph, and discusses some constraints with task assignment. The basic concept is to evaluate the feasible and infea-sible solutions respectively. It evaluates the feasible solutions according to the value of the objective function and the infeasible ones according to the degree of the violation of the constraints. The individual coding is showed by the matrix and the multiple task is solved under the help of target orders. In order to reduce the problem complexity, the weapon types are bind to the targets. Then this paper designs special selection, crossover, inverse and mutation operations, ensures the new chromosomes meet the same constraints as the coding. At last, experiments are made and simulation results show the feasibility and effectiveness of this approach to resolve complex task assignment.

  5. Hybrid Constraints of Pure and Mixed Pixels for Soft-Then-Hard Super-Resolution Mapping with Multiple Shifted Images

    NARCIS (Netherlands)

    Chen, Yuehong; Ge, Yong; Heuvelink, G.B.M.; Hu, Jianlong; Jiang, Yu

    2015-01-01

    Multiple shifted images (MSIs) have been widely applied to many super-resolution mapping (SRM) approaches to improve the accuracy of fine-scale land-cover maps. Most SRM methods with MSIs involve two processes: subpixel sharpening and class allocation. Complementary information from the MSIs has

  6. Hybrid Constraints of Pure and Mixed Pixels for Soft-Then-Hard Super-Resolution Mapping with Multiple Shifted Images

    NARCIS (Netherlands)

    Chen, Yuehong; Ge, Yong; Heuvelink, G.B.M.; Hu, Jianlong; Jiang, Yu

    2015-01-01

    Multiple shifted images (MSIs) have been widely applied to many super-resolution mapping (SRM) approaches to improve the accuracy of fine-scale land-cover maps. Most SRM methods with MSIs involve two processes: subpixel sharpening and class allocation. Complementary information from the MSIs has

  7. Analysis of Multiple-Impact Ballistic Performance of a Tempered Glass Laminate with a Strike Face Film

    Science.gov (United States)

    2014-02-01

    strengthened glass as exterior or strike faces. Initial impact by a single projectile typically produces a quasi-symmetrical crater exhibiting the typical...during subsequent impacts. Should an impact from a second projectile occur on the damaged glass , loosely constrained fragments would be forced in a...Should an impact from a second projectile occur on the damaged glass , loosely constrained fragments would be forced in a direction away from the strike

  8. An algorithm for the path-planning with multiple constraints%一种多约束条件下路径规划算法研究

    Institute of Scientific and Technical Information of China (English)

    李汉轩; 李志华; 吕春生

    2012-01-01

    针对目前导航系统中重要的多约束条件下路径规划功能,结合A*算法和蚁群算法提出一种新的不确定算法,该算法首先将多约束条件进行融合使其适合蚁群转移,并在基本蚁群算法基础上采用了A*算法的评估指标,为蚁群转移时提供最优预测收敛点。通过实验证明该算法可以大幅度降低时间消耗,并且全局收敛性强,计算结果稳定。%In view of the important path planning function under multi-constraint conditions in current navigation systems,a new uncertainty algorithm is proposed which is the connection of A* algorithm and ant Colony algorithm.To adapt transfer of ant Colony algorithm,firstly,multiple constraints is integrated.Then,I took use of the concept of evaluation indicators in A* algorithm to get the optimal forecast convergence point for ant colony transfer.Basing on above operation,the results show that the algorithn has,strong global convergence,and substantially reduced time consumption.

  9. When does female multiple mating evolve to adjust inbreeding? Effects of inbreeding depression, direct costs, mating constraints, and polyandry as a threshold trait.

    Science.gov (United States)

    Duthie, A Bradley; Bocedi, Greta; Reid, Jane M

    2016-09-01

    Polyandry is often hypothesized to evolve to allow females to adjust the degree to which they inbreed. Multiple factors might affect such evolution, including inbreeding depression, direct costs, constraints on male availability, and the nature of polyandry as a threshold trait. Complex models are required to evaluate when evolution of polyandry to adjust inbreeding is predicted to arise. We used a genetically explicit individual-based model to track the joint evolution of inbreeding strategy and polyandry defined as a polygenic threshold trait. Evolution of polyandry to avoid inbreeding only occurred given strong inbreeding depression, low direct costs, and severe restrictions on initial versus additional male availability. Evolution of polyandry to prefer inbreeding only occurred given zero inbreeding depression and direct costs, and given similarly severe restrictions on male availability. However, due to its threshold nature, phenotypic polyandry was frequently expressed even when strongly selected against and hence maladaptive. Further, the degree to which females adjusted inbreeding through polyandry was typically very small, and often reflected constraints on male availability rather than adaptive reproductive strategy. Evolution of polyandry solely to adjust inbreeding might consequently be highly restricted in nature, and such evolution cannot necessarily be directly inferred from observed magnitudes of inbreeding adjustment. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  10. Addressing barriers to the prevention, diagnosis and treatment of hepatitis B and C in the face of persisting fiscal constraints in Europe: report from a high level conference.

    Science.gov (United States)

    Papatheodoridis, G; Thomas, H C; Golna, C; Bernardi, M; Carballo, M; Cornberg, M; Dalekos, G; Degertekin, B; Dourakis, S; Flisiak, R; Goldberg, D; Gore, C; Goulis, I; Hadziyannis, S; Kalamitsis, G; Kanavos, P; Kautz, A; Koskinas, I; Leite, B R; Malliori, M; Manolakopoulos, S; Matičič, M; Papaevangelou, V; Pirona, A; Prati, D; Raptopoulou-Gigi, M; Reic, T; Robaeys, G; Schatz, E; Souliotis, K; Tountas, Y; Wiktor, S; Wilson, D; Yfantopoulos, J; Hatzakis, A

    2016-02-01

    In the WHO-EURO region, around 28 million people are currently living with chronic viral hepatitis, and 120,000 people die every year because of it. Lack of awareness and understanding combined with the social stigma and discrimination exacerbate barriers related to access to prevention, diagnosis and treatment services for those most in need. In addition, the persisting economic crisis has impacted on public health spending, thus posing challenges on the sustainable investment in promotion, primary and secondary prevention, diagnosis and treatment of viral hepatitis across European countries. The Hepatitis B and C Public Policy Association in cooperation with the Hellenic Center for Disease Prevention and Control together with 10 partner organizations discussed at the Athens High Level Meeting held in June 2014 recent policy developments, persisting and emerging challenges related to the prevention and management of viral hepatitis and the need for a de minimis framework of urgent priorities for action, reflected in a Call to Action (Appendix S1). The discussion confirmed that persisting barriers do not allow the full realisation of the public health potential of diagnosing and preventing hepatitis B and C, treating hepatitis B and curing hepatitis C. Such barriers are related to (a) lack of evidence-based knowledge of hepatitis B and C, (b) limited access to prevention, diagnosis and treatment services with poor patient pathways, (c) declining resources and (d) the presence of social stigma and discrimination. The discussion also confirmed the emerging importance of fiscal constraints on the ability of policymakers to adequately address viral hepatitis challenges, particularly through increasing coverage of newer therapies. In Europe, it is critical that public policy bodies urgently agree on a conceptual framework for addressing the existing and emerging barriers to managing viral hepatitis. Such a framework would ensure all health systems share a common

  11. The systematics of strong lens modeling quantified: the effects of constraint selection and redshift information on magnification, mass, and multiple image predictability

    CERN Document Server

    Johnson, Traci L

    2016-01-01

    Until now, systematic errors in strong gravitational lens modeling have been acknowledged but never been fully quantified. Here, we launch an investigation into the systematics induced by constraint selection. We model the simulated cluster Ares 362 times using random selections of image systems with and without spectroscopic redshifts and quantify the systematics using several diagnostics: image predictability, accuracy of model-predicted redshifts, enclosed mass, and magnification. We find that for models with $>15$ image systems, the image plane rms does not decrease significantly when more systems are added; however the rms values quoted in the literature may be misleading as to the ability of a model to predict new multiple images. The mass is well constrained near the Einstein radius in all cases, and systematic error drops to $10$ image systems. Magnification errors are smallest along the straight portions of the critical curve, and the value of the magnification is systematically lower near curved por...

  12. Constraints on grain size and stable iron phases in the uppermost Inner Core from multiple scattering modeling of seismic velocity and attenuation

    CERN Document Server

    Calvet, Marie

    2008-01-01

    We propose to model the uppermost inner core as an aggregate of randomly oriented anisotropic ``patches''. A patch is defined as an assemblage of a possibly large number of crystals with identically oriented crystallographic axes. This simple model accounts for the observed velocity isotropy of short period body waves, and offers a reasonable physical interpretation for the scatterers detected at the top of the inner core. From rigorous multiple scattering modeling of seismic wave propagation through the aggregate, we obtain strong constraints on both the size and the elastic constants of iron patches. We perform a systematic search for iron models compatible with measured seismic velocities and attenuations. An iron model is characterized by its symmetry (cubic or hexagonal), elastic constants, and patch size. Independent of the crystal symmetry, we infer a most likely size of patch of the order of 400 m. Recent {\\it bcc} iron models from the literature are in very good agreement with the most probable elast...

  13. A leader-follower-interactive method for regional water resources management with considering multiple water demands and eco-environmental constraints

    Science.gov (United States)

    Chen, Yizhong; Lu, Hongwei; Li, Jing; Ren, Lixia; He, Li

    2017-05-01

    This study presents the mathematical formulation and implementations of a synergistic optimization framework based on an understanding of water availability and reliability together with the characteristics of multiple water demands. This framework simultaneously integrates a set of leader-followers-interactive objectives established by different decision makers during the synergistic optimization. The upper-level model (leader's one) determines the optimal pollutants discharge to satisfy the environmental target. The lower-level model (follower's one) accepts the dispatch requirement from the upper-level one and dominates the optimal water-allocation strategy to maximize economic benefits representing the regional authority. The complicated bi-level model significantly improves upon the conventional programming methods through the mutual influence and restriction between the upper- and lower-level decision processes, particularly when limited water resources are available for multiple completing users. To solve the problem, a bi-level interactive solution algorithm based on satisfactory degree is introduced into the decision-making process for measuring to what extent the constraints are met and the objective reaches its optima. The capabilities of the proposed model are illustrated through a real-world case study of water resources management system in the district of Fengtai located in Beijing, China. Feasible decisions in association with water resources allocation, wastewater emission and pollutants discharge would be sequentially generated for balancing the objectives subject to the given water-related constraints, which can enable Stakeholders to grasp the inherent conflicts and trade-offs between the environmental and economic interests. The performance of the developed bi-level model is enhanced by comparing with single-level models. Moreover, in consideration of the uncertainty in water demand and availability, sensitivity analysis and policy analysis are

  14. Face Image Analysis Based on Multiple Separated Component Sparse Coding%基于多分离部件稀疏编码的人脸图像分析

    Institute of Scientific and Technical Information of China (English)

    刘伟锋; 刘红丽; 王延江

    2013-01-01

    Considering the different contributions of different facial components to face analysis, e. g. eyes, mouth etc. , a face analysis based on multi-component sparse coding is proposed. Firstly, some facial components which play important role to face analysis are selected. Then, the dictionaries of multiple components are learnt by using multi-view sparse coding algorithm, and the sparse codes of each face image are computed based on the dictionary. The final decision is made through pooling the sparse codes into support vector machines and least squares classifiers. Face analysis experiments include face recognition, facial expression recognition, face recognition with occlusion, and facial expression recognition with occlusion. The experimental results show that the proposed method based on multi-component sparse coding learns optimal weights of different facial components and outperforms single facial component method and simple multi-component fusion method.%考虑到不同部件(眼睛,嘴等)对人脸分析的贡献差别,提出基于多部件稀疏编码的人脸图像分析方法。首先,选取对人脸(表情)分析影响较大的几个人脸部件,然后,利用多视角稀疏编码方法学习各部件的字典,并计算相应的稀疏编码,最后,将稀疏编码输入分类器(支持向量机和最小均方误差)进行判决。分别在数据库JAFFE和Yale上进行人脸(表情)识别及有遮挡的人脸(表情)识别实验。实验结果表明,基于多部件稀疏编码的人脸分析能较好地调节各部件的权重,优于各单一部件和简单的多部件融合方法的性能。

  15. A single-machine scheduling problem with multiple unavailability constraints: A mathematical model and an enhanced variable neighborhood search approach

    Directory of Open Access Journals (Sweden)

    Maziar Yazdani

    2017-01-01

    Full Text Available This research focuses on a scheduling problem with multiple unavailability periods and distinct due dates. The objective is to minimize the sum of maximum earliness and tardiness of jobs. In order to optimize the problem exactly a mathematical model is proposed. However due to computational difficulties for large instances of the considered problem a modified variable neighborhood search (VNS is developed. In basic VNS, the searching process to achieve to global optimum or near global optimum solution is totally random, and it is known as one of the weaknesses of this algorithm. To tackle this weakness, a VNS algorithm is combined with a knowledge module. In the proposed VNS, knowledge module extracts the knowledge of good solution and save them in memory and feed it back to the algorithm during the search process. Computational results show that the proposed algorithm is efficient and effective.

  16. Toward design of multiple-property inorganic-organic hybrid compounds based on face-sharing octahedral iodoplumbate chains.

    Science.gov (United States)

    Zhao, Shun-Ping; Ren, Xiao-Ming

    2011-09-07

    In this review article, we have illustrated the strategies developed to achieve inorganic-organic hybrid compounds with technologically important physical properties. A series of target inorganic-organic hybrid compounds have been accomplished by incorporating the functional organic components (with a large hyperpolarizability and luminophore Schiff base cation) into the highly polarizable one-dimensional (1-D) iodoplumbate chain network. The effect of substituent features in the phenyl ring of the Schiff base cation on its molecular conformation as well as the crystal packing structure of the hybrid compound will be discussed and the multiple physical properties (ferroelectricity, NLO and multiple band emission) will also be mentioned. This journal is © The Royal Society of Chemistry 2011

  17. Multiple constraint modeling of nutrient cycling stoichiometry following forest clearing and pasture abandonment in the Eastern Amazon

    Science.gov (United States)

    Davidson, Eric; Nifong, Rachel

    2017-04-01

    While deforestation has declined since its peak, land-use change continues to modify Amazonian landscapes. The responses and feedbacks of biogeochemical cycles to these changes play an important role in determining possible future trajectories of ecosystem function and for land stewardship through effects on rates of secondary forest regrowth, soil emissions of greenhouse gases, inputs of nutrients to groundwater and streamwater, and nutrient management in agroecosystems. Here we present a new synthetic analyses of data from the NASA-supported LBA-ECO project and others datasets on nutrient cycling in cattle pastures, secondary forests, and mature forests at Paragominas, Pará, Brazil. We have developed a stoichiometric model relating C-N-P interactions during original forest clearing, extensive and intensive pasture management, and secondary forest regrowth, constrained by multiple observations of ecosystem stocks and fluxes in each land use. While P is conservatively cycled in all land uses, we demonstrate that pyrolyzation of N during pasture formation and during additional burns for pasture management depletes available-N pools, consistent with observations of lower rates of N leaching and trace gas emission and consistent with secondary forest growth responses to experimental N amendments. The soils store large stocks of N and P, and our parameterization of available forms of these nutrients for steady-state dynamics in the mature forest yield reasonable estimates of net N and P mineralization available for grasses and secondary forest species at rates consistent with observed biomass accumulation and productivity in these modified ecosystems. Because grasses and forests have much different demands for N relative to P, the land use has important biogeochemical impacts. The model demonstrates the need for periodic P inputs for sustainable pasture management and for a period of significant biological N fixation for early-to-mid-successional secondary forest

  18. Constraint Differentiation

    DEFF Research Database (Denmark)

    Mödersheim, Sebastian Alexander; Basin, David; Viganò, Luca

    2010-01-01

    , under the assumption that the original constraint-based approach has these properties. Practically, as a concrete case study, we have integrated this technique into OFMC, a state-of-the-art model-checker for security protocol analysis, and demonstrated its effectiveness by extensive experimentation. Our......We introduce constraint differentiation, a powerful technique for reducing search when model-checking security protocols using constraint-based methods. Constraint differentiation works by eliminating certain kinds of redundancies that arise in the search space when using constraints to represent...

  19. Scheduling multiple orders per job with various constraints for hybrid flow shop%考虑多约束的混合流水车间MOJ调度

    Institute of Scientific and Technical Information of China (English)

    周炳海; 王腾

    2016-01-01

    With a comprehensive consideration of multiple product types and sequence-dependent setup times constraints in which processes of wafer fabrications, a scheduling model of multiple orders per job(MOJ) in a hybrid flow shop with an objective function of minimizing total completion time of the system is developed. On the basis of the descriptions, a column generation algorithm based on the job-product-machine three level disjunctive network flow is proposed. Furthermore, to improve the degradation effects of column generation algorithm, Lagrangian relaxation with sub-gradient optimization is combined into the frame of column generation algorithm, and then a modified column generation(MCG) algorithm adopting dual iteration is proposed. Finally, theory analysis and simulation experiments show that the developed MCG algorithm is valid and feasible.%考虑晶圆加工过程中的多品种和与次序相关的换模时间约束,以系统总完工时间最小为优化目标,建立混合流水车间MOJ调度模型。在此基础上,提出了基于作业-产品-机器三层析取网络流的列生成算法。为进一步改善列生成算法存在的尾效应,将基于次梯度优化的拉格朗日松弛算法嵌入列生成算法框架中,构建了采用双重迭代的改进型列生成(MCG)算法。最后,通过理论分析和仿真实验表明了MCG算法是有效、可行的。

  20. Investigating the Multiple Food Sources and N Chemistry of Invasive Earthworms at the Rhinelander, WI, Free Air CO2 Enrichment (FACE) Experiment

    Science.gov (United States)

    Top, S. M.; Filley, T. R.

    2013-12-01

    Rising levels of atmospheric CO2 can directly and indirectly alter biogeochemical cycling in forest ecosystems through changes to plant productivity, tissue chemistry, and associated feedbacks to microbial and faunal communities. At the Rhinelander free air CO2 enrichment site (FACE), Rhinelander WI, we examined the consumption and movement of plant tissue and soil by invasive earthworm species using a multi-proxy stable isotope and amino acid chemistry analysis of plant and soil, as well as fecal matter extracted from invasive earthworms present at the site. Using an isotopic mixing model that exploits the 13C-depleted CO2 source and a previous 15N labeling in the FACE experiment, we determined potential sources to the earthworm fecal matter and the movement of amino compounds. For epigeic, surface dwelling earthworms, the stable isotope modeling showed the largest contribution to the C and N in fecal matter was from leaf litter (up to 80%) which was depleted in amino acid C under elevated CO2 conditions. Fecal matter from the endogeic, mineral soil dwelling earthworms was primarily derived from 0-5 cm soil (up to 56%) and fine root tissue (up to 70%). Additionally, amino acid C in this group of earthworms had a proportionately greater relative concentration compared to the epigeic species and the 0-5cm soil. Here we demonstrate that earthworms are incorporating multiple sources (leaf litter, root, and soil) into their fecal matter, which then get deposited throughout the soil profile, where nutrients could become available for plant use.

  1. Schematic Road Network Map Progressive Generalization Based on Multiple Constraints%多约束条件下示意性道路网地图渐进式综合

    Institute of Scientific and Technical Information of China (English)

    董卫华; 郭庆胜; 刘纪平

    2008-01-01

    Multiple constraints for schematic road network map cartographic design are analyzed and summarized. Based on this, a set of quantitative criteria are set up and a new road network generalization method including progressive selection and displacement is proposed. Furthermore, topological checking methods for road networks are researched. Based on these constraints, the points in a road network are classified, and a satisfactory and effective schematic map is designed in a concrete experiment while maintaining topological consistency of the road network between the original and the schematic map.

  2. Object-based 3D geomodel with multiple constraints for early Pliocene fan delta in the south of Lake Albert Basin, Uganda

    Science.gov (United States)

    Wei, Xu; Lei, Fang; Xinye, Zhang; Pengfei, Wang; Xiaoli, Yang; Xipu, Yang; Jun, Liu

    2017-01-01

    The early Pliocene fan delta complex developed in the south of Lake Albert Basin which is located at the northern end of the western branch in the East African Rift System. The stratigraphy of this succession is composed of distributary channels, overbank, mouthbar and lacustrine shales. Limited by the poor seismic quality and few wells, it is full of challenge to delineate the distribution area and patterns of reservoir sands. Sedimentary forward simulation and basin analogue were applied to analyze the spatial distribution of facies configuration and then a conceptual sedimentary model was constructed by combining with core, heavy mineral and palynology evidences. A 3D geological model of a 120 m thick stratigraphic succession was built using well logs and seismic surfaces based on the established sedimentary model. The facies modeling followed a hierarchical object-based approach conditioned to multiple trend constraints like channel intensity, channel azimuth and channel width. Lacustrine shales were modeled as background facies and then in turn eroded by distribute channels, overbank and mouthbar respectively. At the same time a body facies parameter was created to indicate the connectivity of the reservoir sands. The resultant 3D facies distributions showed that the distributary channels flowed from east bounding fault to west flank and overbank was adhered to the fringe of channels while mouthbar located at the end of channels. Furthermore, porosity and permeability were modeled using sequential Gaussian simulation (SGS) honoring core observations and petrophysical interpretation results. Despite the poor seismic is not supported to give enough information for fan delta sand distribution, creating a truly representative 3D geomodel is still able to be achieved. This paper highlights the integration of various data and comprehensive steps of building a consistent representative 3D geocellular fan delta model used for numeral simulation studies and field

  3. Face pain

    Science.gov (United States)

    ... begin in other places in the body. Abscessed tooth (ongoing throbbing pain on one side of the lower face that ... face, and aggravated by eating. Call a dentist. Pain is persistent, ... by other unexplained symptoms. Call your primary provider.

  4. Bayesian Face Sketch Synthesis.

    Science.gov (United States)

    Wang, Nannan; Gao, Xinbo; Sun, Leiyu; Li, Jie

    2017-03-01

    Exemplar-based face sketch synthesis has been widely applied to both digital entertainment and law enforcement. In this paper, we propose a Bayesian framework for face sketch synthesis, which provides a systematic interpretation for understanding the common properties and intrinsic difference in different methods from the perspective of probabilistic graphical models. The proposed Bayesian framework consists of two parts: the neighbor selection model and the weight computation model. Within the proposed framework, we further propose a Bayesian face sketch synthesis method. The essential rationale behind the proposed Bayesian method is that we take the spatial neighboring constraint between adjacent image patches into consideration for both aforementioned models, while the state-of-the-art methods neglect the constraint either in the neighbor selection model or in the weight computation model. Extensive experiments on the Chinese University of Hong Kong face sketch database demonstrate that the proposed Bayesian method could achieve superior performance compared with the state-of-the-art methods in terms of both subjective perceptions and objective evaluations.

  5. Hierarchical Spatio-Temporal Probabilistic Graphical Model with Multiple Feature Fusion for Binary Facial Attribute Classification in Real-World Face Videos.

    Science.gov (United States)

    Demirkus, Meltem; Precup, Doina; Clark, James J; Arbel, Tal

    2016-06-01

    Recent literature shows that facial attributes, i.e., contextual facial information, can be beneficial for improving the performance of real-world applications, such as face verification, face recognition, and image search. Examples of face attributes include gender, skin color, facial hair, etc. How to robustly obtain these facial attributes (traits) is still an open problem, especially in the presence of the challenges of real-world environments: non-uniform illumination conditions, arbitrary occlusions, motion blur and background clutter. What makes this problem even more difficult is the enormous variability presented by the same subject, due to arbitrary face scales, head poses, and facial expressions. In this paper, we focus on the problem of facial trait classification in real-world face videos. We have developed a fully automatic hierarchical and probabilistic framework that models the collective set of frame class distributions and feature spatial information over a video sequence. The experiments are conducted on a large real-world face video database that we have collected, labelled and made publicly available. The proposed method is flexible enough to be applied to any facial classification problem. Experiments on a large, real-world video database McGillFaces [1] of 18,000 video frames reveal that the proposed framework outperforms alternative approaches, by up to 16.96 and 10.13%, for the facial attributes of gender and facial hair, respectively.

  6. 多视觉环境下联合多约束的三维目标体重建%3D voxel reconstruction under multiple constraints in multi-view environment

    Institute of Scientific and Technical Information of China (English)

    陈宁; 李秀秀; 郑江滨

    2011-01-01

    提出了一种联合多种约束条件的体元重建方法.首先将场景空间离散为体元,并从多视获取的二维图像中提取目标轮廓信息;其次利用侧影轮廓约束及颜色一致性约束,恢复目标三维信息;针对重建模型存在漂浮体元和毛刺现象,提出加入平滑约束解决该问题;最后提出模型修复算法对模型表面空洞进行填补,解决重建模型空洞问题.实验结果表明,该方法可重建颜色纹理信息准确的目标外形,且模型光滑细腻,表面空洞得到有效填补.%A new voxel reconstruction under multiple constraints was proposed.Firstly, the scene was discreted to voxel,and target silhouette information was extracted in multi-view-obtained 2D image.Secondly, two constraints were used to recover target 3 D information, which were silhouette constraint and the color consistency constraint.Smooth constrict was used to solve the problem that reconstructed model had float voxel and glitch.Based on the composition of the three forces, the floating voxels and the burrs could be restrained efficiently.Finally, a model recovering algorithm was proposed to fill the holes on the surface of the reconstructed model.The experimental results demonstrate that the method can reconstruct the target appearance with correct color and texture information, also the model is smooth and delicate, thus the hole can be filled effectively.

  7. About Face

    Medline Plus

    Full Text Available Skip to Content Menu Closed (Tap to Open) Home Videos by Topic Videos by Type Search All ... What is AboutFace? Resources for Professionals Get Help Home Watch Videos by Topic Videos by Type Search ...

  8. About Face

    Medline Plus

    Full Text Available ... Home Videos by Topic Videos by Type Search All Videos PTSD Basics PTSD Treatment What is AboutFace? ... Watch Videos by Topic Videos by Type Search All Videos Learn More PTSD Basics PTSD Treatment What ...

  9. Multibiometrics for face recognition

    NARCIS (Netherlands)

    Veldhuis, Raymond; Deravi, Farzin; Tao, Qian

    2008-01-01

    Fusion is a popular practice to combine multiple sources of biometric information to achieve systems with greater performance and flexibility. In this paper various approaches to fusion within a multibiometrics context are considered and an application to the fusion of 2D and 3D face information is

  10. Multibiometrics for face recognition

    NARCIS (Netherlands)

    Veldhuis, Raymond N.J.; Deravi, Farzin; Tao, Q.

    Fusion is a popular practice to combine multiple sources of biometric information to achieve systems with greater performance and flexibility. In this paper various approaches to fusion within a multibiometrics context are considered and an application to the fusion of 2D and 3D face information is

  11. 使用稀疏约束非负矩阵分解算法的跨年龄人脸识别%An age-span face recognition method based on an NMF algorithm with sparseness constraints

    Institute of Scientific and Technical Information of China (English)

    杜吉祥; 翟传敏; 叶永青

    2012-01-01

    人脸识别技术中除光线、姿态、表情因素外,由于年龄变化而导致的人脸形状和纹理上的变化会极大程度地影响人脸识别系统性能.对此,提出了一种使用稀疏非负矩阵分解算法来实现人脸老化模拟,然后将此方法应用于具有年龄跨度的人脸识别上,通过模拟虚拟样本来增强识别效果.实验结果表明,年龄跨度对人脸识别的确有较大的影响;当系数矩阵保持稀疏时,非负矩阵分解算法具有更强的特征提取能力;经过老化模拟增加虚拟样本后,其纹理老化效果明显地提高了跨年龄段的人脸识别的性能.%For face recognition technology, apart from lighting, gesture, and expression factors, variations in shape and texture of human faces due to aging factors also significantly affect the performance of face recognition systems. Using a sparse-constrained non-negative matrix factorization (NMF) algorithm, a facial aging simulation method based on an improved prototype was first proposed and then applied to age-span face recognition to add virtual samples and heighten the recognition rate. Experimental results show that the age span indeed has a great effect on face recognition; the NMF algorithm has stronger feature extraction ability when the coefficient matrix is sparsely constrained. Furthermore, the recognition ratio is apparently improved after adding additional virtual samples by aging simulation of face texture features.

  12. Face Forward

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Last November, surgeons in France successfully performed the world's first face transplant surgery. Ten days later, Chen Huanran in Beijing began soliciting patients who were ready to accept a face transplant, searching for China's first such patient through an advertisement on his website and other channels. Chen, chief orthopedic surgeon at the Plastic Surgery Hospital under the Chinese Academy of Medical Sciences, has conducted more than 300 transsexual operations and was considered one of the top com...

  13. 面孔多次与单次呈现对女性再认优势的调节%Multiple Times Appearance and Single Time Appearance of Faces Regulating Women's Recognition Advantage

    Institute of Scientific and Technical Information of China (English)

    蒋重清; 陈晓宇

    2015-01-01

    本研究采用"学习—再认"的范式,招募58名大学生作为参与者,研究不同频次的面孔呈现方式,对不同性别参与者的面孔再认成绩的影响.实验结果发现:加工阶段多次呈现的面孔的再认成绩好于单次呈现面孔的再认成绩;学习阶段面孔多次呈现条件下,女性的面孔再认成绩好于男性的面孔再认成绩.实验结果说明:在面孔呈现总时长相等的情况下,学习阶段多次呈现面孔,可以使个体对面孔进行多次编码,有利于随后的面孔再认;面孔再认成绩可能依赖于加工阶段对面孔编码的精细程度;相比于男性,女性的较好语言能力和较丰富的面孔经验有助于其在加工阶段对面孔进行精细加工,进而使其获得面孔再认优势.%Based on the"Learning-recognition" paradigm,the study recruited 58 university students (29 fe-males) taking part in the experiment to explore the influence of different facial appearance frequency on their facial recognition performance.The results showed that the facial recognition performance was better when faces were appeared multiple times than single time.And there were also an interaction between dif-ferent facial appearance frequency and the gender of participants on the facial recognition performance.In the condition of multiple times appearance of faces during learning,females' facial recognition performance was better than males'.The results suggested in the case that the total length of face appearance time was equal,multiple times appearance of faces during learning could make the individual to code face many times,which was conducive to the subsequent facial recognition.The facial recognition performance might rely on the precision stage of face encoding during learning.And compared with males,females' better a-bility of language and richer face experience were conducive to the precision processing of faces during learning and then made them gain face recognition advantage.

  14. About Face

    Medline Plus

    Full Text Available ... PTSD (posttraumatic stress disorder). Watch the intro This is AboutFace In these videos, Veterans, family members, and ... to hear what they have to say. What is PTSD? → How does PTSD affect loved ones? → Am ...

  15. About Face

    Medline Plus

    Full Text Available ... traumatic event — like combat, an assault, or a disaster — it's normal to feel scared, keyed up, or sad at first. But if it's been months or years since the trauma and you're not feeling better, you may have PTSD (posttraumatic stress disorder). Watch the intro This is AboutFace In ...

  16. Optimal Routing and Control of Multiple Agents Moving in a Transportation Network and Subject to an Arrival Schedule and Separation Constraints

    Science.gov (United States)

    Sadovsky, A. V.; Davis, D.; Isaacson, D. R.

    2012-01-01

    We address the problem of navigating a set of moving agents, e.g. automated guided vehicles, through a transportation network so as to bring each agent to its destination at a specified time. Each pair of agents is required to be separated by a minimal distance, generally agent-dependent, at all times. The speed range, initial position, required destination, and required time of arrival at destination for each agent are assumed provided. The movement of each agent is governed by a controlled differential equation (state equation). The problem consists in choosing for each agent a path and a control strategy so as to meet the constraints and reach the destination at the required time. This problem arises in various fields of transportation, including Air Traffic Management and train coordination, and in robotics. The main contribution of the paper is a model that allows to recast this problem as a decoupled collection of problems in classical optimal control and is easily generalized to the case when inertia cannot be neglected. Some qualitative insight into solution behavior is obtained using the Pontryagin Maximum Principle. Sample numerical solutions are computed using a numerical optimal control solver.

  17. Online blind source separation using incremental nonnegative matrix factorization with volume constraint.

    Science.gov (United States)

    Zhou, Guoxu; Yang, Zuyuan; Xie, Shengli; Yang, Jun-Mei

    2011-04-01

    Online blind source separation (BSS) is proposed to overcome the high computational cost problem, which limits the practical applications of traditional batch BSS algorithms. However, the existing online BSS methods are mainly used to separate independent or uncorrelated sources. Recently, nonnegative matrix factorization (NMF) shows great potential to separate the correlative sources, where some constraints are often imposed to overcome the non-uniqueness of the factorization. In this paper, an incremental NMF with volume constraint is derived and utilized for solving online BSS. The volume constraint to the mixing matrix enhances the identifiability of the sources, while the incremental learning mode reduces the computational cost. The proposed method takes advantage of the natural gradient based multiplication updating rule, and it performs especially well in the recovery of dependent sources. Simulations in BSS for dual-energy X-ray images, online encrypted speech signals, and high correlative face images show the validity of the proposed method.

  18. Multiple sulfur isotope constraints on sulfate-driven anaerobic oxidation of methane: Evidence from authigenic pyrite in seepage areas of the South China Sea

    Science.gov (United States)

    Lin, Zhiyong; Sun, Xiaoming; Strauss, Harald; Lu, Yang; Gong, Junli; Xu, Li; Lu, Hongfeng; Teichert, Barbara M. A.; Peckmann, Jörn

    2017-08-01

    Multiple sulfur isotope signatures and secondary ion mass spectroscopy (SIMS) sulfur isotope compositions of pyrite from two seafloor sites (DH-CL11 and HD109) in seepage areas of the South China Sea were measured in order to study isotope effects of sulfate-driven anaerobic oxidation of methane (SO4-AOM). The multiple sulfur isotopes of pyrite reveal variable ranges for both sites (δ34S: between -44.1‰ and -2.9‰ for DH-CL11 and between -43.8‰ and -1.6‰ for HD109; Δ33S: between 0.02‰ and 0.17‰ for DH-CL11 and between -0.03‰ and 0.14‰ for HD109). SIMS analysis reveals an extreme variability of δ34S values (between -50.3‰ and -2.7‰ in DH-CL11; between -50.1 and 52.4‰ in HD109) for three types of pyrite: (1) framboids, (2) zoned aggregates with radial overgrowth surrounding a framboidal core, and (3) euhedral pyrite crystals. The synchronous changes of geochemical proxies (sulfate and methane concentrations, δ34Ssulfate and δ18Osulfate, δ34Spyrite, and pyrite content) at the sulfate-methane transition zone (SMTZ) at site DH-CL11 are interpreted to be induced by SO4-AOM under steady state conditions. In contrast, pyrite content and δ34S value fluctuations throughout core HD109 suggest that the sediment at this site was affected by multiple pyritization events during diagenesis. Multiple sulfur isotope signatures of early diagenetic pyrite (i.e., with low and high δ34S values, the latter above 315 cmbsf in DH-CL11; above 70 cmbsf in HD109) in the upper sediment column suggest that organoclastic sulfate reduction (OSR) and sulfur disproportionation generated the observed isotopic signatures. In contrast to the early diagenetic 34S depleted framboids, the higher SIMS δ34S values of overgrowth and euhedral crystals suggest a late diagenetic 34S enriched pool of dissolved sulfide derived from SO4-AOM at the current and paleo-SMTZs. Interestingly, pyrite resulting from SO4-AOM in the SMTZ at site DH-CL11 reveals a distinct pattern with higher

  19. Reading faces and Facing words

    DEFF Research Database (Denmark)

    Robotham, Julia Emma; Lindegaard, Martin Weis; Delfi, Tzvetelina Shentova

    It has long been argued that perceptual processing of faces and words is largely independent, highly specialised and strongly lateralised. Studies of patients with either pure alexia or prosopagnosia have strongly contributed to this view. The aim of our study was to investigate how visual...

  20. Reading faces and Facing words

    DEFF Research Database (Denmark)

    Robotham, Julia Emma; Lindegaard, Martin Weis; Delfi, Tzvetelina Shentova

    performed within normal range on at least one test of visual categorisation, strongly suggesting that their abnormal performance with words and faces does not represent a generalised visuo-perceptual deficit. Our results suggest that posterior areas in both hemispheres may be critical for both reading...

  1. Quantified Faces

    DEFF Research Database (Denmark)

    Sørensen, Mette-Marie Zacher

    2016-01-01

    Abstract: The article presents three contemporary art projects that, in various ways, thematise questions regarding numerical representation of the human face in relation to the identification of faces, for example through the use of biometric video analysis software, or DNA technology. The Dutch...... and critically examine bias in surveillance technologies, as well as scientific investigations, regarding the stereotyping mode of the human gaze. The American artist Heather Dewey-Hagborg creates three-dimensional portraits of persons she has “identified” from their garbage. Her project from 2013 entitled....... The three works are analysed with perspectives to historical physiognomy and Francis Galton's composite portraits from the 1800s. It is argued that, rather than being a statistical compression like the historical composites, contemporary statistical visual portraits (composites) are irreversible...

  2. (non) Emergent Constraints

    Science.gov (United States)

    Jackson, C. S.; Hattab, M. W.; Huerta, G.

    2014-12-01

    Emergent constraints are observable quantities that provide some physical basis for testing or predicting how a climate model will respond to greenhouse gas forcing. Very few such constraints have been identified for the multi-model CMIP archive. Here we explore the question of whether constraints that apply to a single model, a perturbed parameter ensemble (PPE) of the Community Atmosphere Model (CAM3.1), can be applied to predicting the climate sensitivities of models within the CMIP archive. In particular we construct our predictive patterns from multivariate EOFs of the CAM3.1 ensemble control climate. Multiple regressive statistical models were created that do an excellent job of predicting CAM3.1 sensitivity to greenhouse gas forcing. However, these same patterns fail spectacularly to predict sensitivities of models within the CMIP archive. We attribute this failure to several factors. First, and perhaps the most important, is that the structures affecting climate sensitivity in CAM3.1 have a unique signature in the space of our multivariate EOF patterns that are unlike any other climate model. That is to say, we should not expect CAM3.1 to represent the way another models within CMIP archive respond to greenhouse gas forcing. The second, perhaps related, reason is that the CAM3.1 PPE does a poor job of spanning the range of climates and responses found within the CMIP archive. We shall discuss the implications of these results for the prospect of finding emergent constraints within the CMIP archive. We will also discuss what this may mean for establishing uncertainties in climate projections.

  3. The multiple faces of the human immune system : Modern life causes low-grade inflammation and thereby provokes conflict between the selfish immune system and the selfish brain

    NARCIS (Netherlands)

    Pruimboom, Leo

    2017-01-01

    This thesis describes the multiple ways by which the human immune system can react upon direct and indirect challenges, such as infection and wounds on the one hand, and chronic stress factors, such as smoking, on the other. The human defense system exhibits a type of selfish behaviour during both a

  4. Fusion of Local and Global Features Using Multiple Kernel Learning for Face Recognition%多核学习融合局部和全局特征的人脸识别算法

    Institute of Scientific and Technical Information of China (English)

    杨赛; 赵春霞; 刘凡

    2016-01-01

    A new face recognition algorithm via bag-of-words(BoW)is proposed.In specific,it uses BoW and the global pattern of BoW respectively as the local feature and global feature of face images.Multiple kernel learning is adopted to fuse the local and global features.Extensive experiments were carried out on four face databases,i.e.AR,FERET,CMU PIE and LFW.The results show that our method can effectively solve the small training size problem and is more robust to expression changes,position variations and occlusion.%提出一种基于词袋模型的新的人脸识别算法.该方法将词袋模型和词袋模型的全局模式分别作为人脸图像的局部特征和全局特征描述,最后使用多核学习方法将二者进行融合.AR、FERET、CMU PIE以及LFW公开人脸数据库上的实验结果表明,本文方法能够更好的解决小样本问题,并且对人脸的表情变化、姿态变化以及面部遮挡具有更优良的鲁棒性.

  5. Integrated batch production and maintenance scheduling for multiple items processed on a deteriorating machine to minimize total production and maintenance costs with due date constraint

    Directory of Open Access Journals (Sweden)

    Zahedi Zahedi

    2016-04-01

    Full Text Available This paper discusses an integrated model of batch production and maintenance scheduling on a deteriorating machine producing multiple items to be delivered at a common due date. The model describes the trade-off between total inventory cost and maintenance cost as the increase of production run length. The production run length is a time bucket between two consecutive preventive maintenance activities. The objective function of the model is to minimize total cost consisting of in process and completed part inventory costs, setup cost, preventive and corrective maintenance costs and rework cost. The problem is to determine the optimal production run length and to schedule the batches obtained from determining the production run length in order to minimize total cost.

  6. Repetition suppression to faces in the fusiform face area: A personal and dynamic journey.

    Science.gov (United States)

    Henson, Richard N

    2016-07-01

    I review a number of fMRI studies that investigate the effects of repeating faces on responses in the fusiform face area (FFA). These studies show that repetition suppression (RS), as well as repetition enhancement (RE), are sensitive to multiple factors, including pre-existing stimulus representations, cognitive task, lag between repetitions and spatial attention. Parallel EEG studies provide additional constraints on the timing of these repetition effects. Together, the results suggest that RS is not a unitary phenomenon, but likely subsumes multiple mechanisms that operate under different conditions. These mechanisms of course need to relate to single-cell data and known physiological mechanisms; but to make further progress, I believe we need dynamical neural network models that relate these mechanisms to the properties of neural populations that are measured by fMRI and EEG data. One example model is sketched, in which RS reflects an acceleration of neural dynamics, owing to reduced prediction error within a recurrent visual processing hierarchy.

  7. How fast is famous face recognition?

    Directory of Open Access Journals (Sweden)

    Gladys eBarragan-Jason

    2012-10-01

    Full Text Available The rapid recognition of familiar faces is crucial for social interactions. However the actual speed with which recognition can be achieved remains largely unknown as most studies have been carried out without any speed constraints. Different paradigms have been used, leading to conflicting results, and although many authors suggest that face recognition is fast, the speed of face recognition has not been directly compared to fast visual tasks. In this study, we sought to overcome these limitations. Subjects performed three tasks, a familiarity categorization task (famous faces among unknown faces, a superordinate categorization task (human faces among animal ones and a gender categorization task. All tasks were performed under speed constraints. The results show that, despite the use of speed constraints, subjects were slow when they had to categorize famous faces: minimum reaction time was 467 ms, which is 180 ms more than during superordinate categorization and 160 ms more than in the gender condition. Our results are compatible with a hierarchy of face processing from the superordinate level to the familiarity level. The processes taking place between detection and recognition need to be investigated in detail.

  8. An Integrated Maintenance Strategy on Two Operating Classes with Multiple Constraints%具有多种约束的两工作等级综合维修策略

    Institute of Scientific and Technical Information of China (English)

    胡智勇; 谢里阳; 孔祥伟; 张晓瑾

    2013-01-01

    Aiming at effective maintenance planning for equipment which has multiple operating classes, an integrated maintenance strategy is proposed in this paper. By using the proposed maintenance strategy, maintenance effect model, and damage accumulation theory, a life cycle benefit model of two operating classes with multiple constraints is established. Numerical example is given to verify the proposed strategy and it shows that is can maximize the life cycle benefit of equipment.%为了制定设备多工作等级维修计划,提出了一种综合维修策略.采用综合维修策略,基于维修效果模型和损伤累积理论,在多种约束条件下,建立了两工作等级设备全寿命周期收益模型.引入数字算例,验证了该策略可以实现设备全寿命周期收益的最大化.

  9. Integrity Constraint Checking in Federated Databases

    NARCIS (Netherlands)

    Grefen, Paul; Widom, Jennifer

    1996-01-01

    A federated database is comprised of multiple interconnected databases that cooperate in an autonomous fashion. Global integrity constraints are very useful in federated databases, but the lack of global queries, global transaction mechanisms, and global concurrency control renders traditional const

  10. Holistic crowding of Mooney faces.

    Science.gov (United States)

    Farzin, Faraz; Rivera, Susan M; Whitney, David

    2009-06-29

    An object or feature is generally more difficult to identify when other objects are presented nearby, an effect referred to as crowding. Here, we used Mooney faces to examine whether crowding can also occur within and between holistic face representations (C. M. Mooney, 1957). Mooney faces are ideal stimuli for this test because no cues exist to distinguish facial features in a Mooney face; to find any facial feature, such as an eye or a nose, one must first holistically perceive the image as a face. Through a series of six experiments we tested the effect of crowding on Mooney face recognition. Our results demonstrate crowding between and within Mooney faces and fulfill the diagnostic criteria for crowding, including eccentricity dependence and lack of crowding in the fovea, critical flanker spacing consistent with less than half the eccentricity of the target, and inner-outer flanker asymmetry. Further, our results show that recognition of an upright Mooney face is more strongly impaired by upright Mooney face flankers than inverted ones. Taken together, these results suggest crowding can occur selectively between high-level representations of faces and that crowding must occur at multiple levels in the visual system.

  11. The genesis of the Hashitu porphyry molybdenum deposit, Inner Mongolia, NE China: constraints from mineralogical, fluid inclusion, and multiple isotope (H, O, S, Mo, Pb) studies

    Science.gov (United States)

    Zhai, Degao; Liu, Jiajun; Tombros, Stylianos; Williams-Jones, Anthony E.

    2017-06-01

    The Hashitu porphyry molybdenum deposit is located in the Great Hinggan Range Cu-Mo-Pb-Zn-Ag polymetallic metallogenic province of NE China, in which the Mo-bearing quartz veins are hosted in approximately coeval granites and porphyries. The deposit contains more than 100 Mt of ore with an average grade of 0.13 wt.% Mo. This well-preserved magmatic-hydrothermal system provides an excellent opportunity to determine the source of the molybdenum, the evolution of the hydrothermal fluids and the controls on molybdenite precipitation in a potentially important but poorly understood metallogenic province. Studies of fluid inclusions hosted in quartz veins demonstrate that the Hashitu hydrothermal system evolved to progressively lower pressure and temperature. Mineralogical and fluid inclusion analyses and physicochemical calculations suggest that molybdenite deposition occurred at a temperature of 285 to 325 °C, a pressure from 80 to 230 bars, a pH from 3.5 to 5.6, and a ∆log fO2 (HM) of -3.0, respectively. Results of multiple isotope (O, H, S, Mo, and Pb) analyses are consistent in indicating a genetic relationship between the ore-forming fluids, metals, and the Mesozoic granitic magmatism (i.e., δ 18OH2O from +1.9 to +9.7‰, δDH2O from -106 to -87‰, δ 34SH2S from +0.3 to +3.9‰, δ 98/95Mo from 0 to +0.37‰, 206Pb/204Pb from 18.2579 to 18.8958, 207Pb/204Pb from 15.5384 to 15.5783, and 208Pb/204Pb from 38.0984 to 42.9744). Molybdenite deposition is interpreted to have occurred from a low-density magmatic-hydrothermal fluid in response to decreases in temperature, pressure, and fO2.

  12. Multiple sulfur isotope and mineralogical constraints on the genesis of Ni-Cu-PGE magmatic sulfide mineralization of the Monchegorsk Igneous Complex, Kola Peninsula, Russia

    Science.gov (United States)

    Bekker, A.; Grokhovskaya, T. L.; Hiebert, R.; Sharkov, E. V.; Bui, T. H.; Stadnek, K. R.; Chashchin, V. V.; Wing, B. A.

    2016-12-01

    We present the results of a pilot investigation of multiple sulfur isotopes for the Ni-Cu-PGE sulfide mineralization of the ˜2.5 Ga Monchegorsk Igneous Complex (MIC). Base Metal Sulfide (BMS) compositions, Platinum Group Element (PGE) distributions, and Platinum Group Mineral (PGM) assemblages were also studied for different types of Ni-Cu-PGE mineralization. The uniformly low S content of the country rocks for the MIC as well as variable Sm-Nd isotope systematics and low-sulfide, PGE-rich mineralization of the MIC suggest that S saturation was reached via assimilation of silicates rather than assimilation of sulfur-rich lithologies. R-factor modeling suggests that the mixing ratio for silicate-to-sulfide melt was very high, well above 15,000 for the majority of our mineralized samples, as might be expected for the low-sulfide, PGE-rich mineralization of the MIC. Small, negative Δ33S values (from -0.23 to -0.04 ‰) for sulfides in strongly metamorphosed MIC-host rocks indicate that their sulfur underwent mass-independent sulfur isotope fractionation (MIF) in the oxygen-poor Archean atmosphere before it was incorporated into the protoliths of the host paragneisses and homogenized during metamorphism. Ore minerals from the MIC have similar Δ33S values (from -0.21 to -0.06 ‰) consistent with country rock assimilation contributing to sulfide saturation, but, also importantly, our dataset suggests that Δ33S values decrease from the center to the margin of the MIC as well as from early to late magmatic phases, potentially indicating that both local assimilation of host rocks and S homogenization in the central part of the large intrusion took place.

  13. FACE RECOGNITION FROM FRONT-VIEW FACE

    Institute of Scientific and Technical Information of China (English)

    WuLifang; ShenLansun

    2003-01-01

    This letter presents a face normalization algorithm based on 2-D face model to rec-ognize faces with variant postures from front-view face.A 2-D face mesh model can be extracted from faces with rotation to left or right and the corresponding front-view mesh model can be estimated according to facial symmetry.Then based on the relationship between the two mesh models,the nrmalized front-view face is formed by gray level mapping.Finally,the face recognition will be finished based on Principal Component Analysis(PCA).Experiments show that better face recognition performance is achieved in this way.

  14. FACE RECOGNITION FROM FRONT-VIEW FACE

    Institute of Scientific and Technical Information of China (English)

    Wu Lifang; Shen Lansun

    2003-01-01

    This letter presents a face normalization algorithm based on 2-D face model to recognize faces with variant postures from front-view face. A 2-D face mesh model can be extracted from faces with rotation to left or right and the corresponding front-view mesh model can be estimated according to the facial symmetry. Then based on the inner relationship between the two mesh models, the normalized front-view face is formed by gray level mapping. Finally, the face recognition will be finished based on Principal Component Analysis (PCA). Experiments show that better face recognition performance is achieved in this way.

  15. Rapidly Developed Multiple Face and Neck Skin Cancers in a Patient with Sjögren’s Syndrome: A Case Report

    Science.gov (United States)

    Teh, Lean San; Lai, Ji-Ching; Lian, Je Chuan

    2017-01-01

    Patient: Male, 76 Final Diagnosis: Skin cancer Symptoms: Skin Medication: — Clinical Procedure: — Specialty: Surgery Objective: Unknown ethiology Background: Sjögren’s syndrome is a chronic, systemic disorder of an autoimmune nature, and its primary etiopathogenetic events are not known. Previous studies have found elevated incidence of malignancies in patients with primary Sjögren’s syndrome. However, there are few reports regarding the association of Sjögren’s syndrome with skin cancers, especially with multiple skin cancers developed within a short time. Case Report: We reported an unusual case of a patient with primary Sjögren’s syndrome who suffered from rapidly developed facial and neck skin cancers within two years. Conclusions: Sjögren’s syndrome associated with skin cancer is rare. Our case report suggests that Sjögren’s syndrome patients require continuous follow-up with conventional cancer examination, including skin biopsy for suspected skin lesions. PMID:28373638

  16. Stochastic Constraint Programming

    OpenAIRE

    Walsh, Toby

    2009-01-01

    To model combinatorial decision problems involving uncertainty and probability, we introduce stochastic constraint programming. Stochastic constraint programs contain both decision variables (which we can set) and stochastic variables (which follow a probability distribution). They combine together the best features of traditional constraint satisfaction, stochastic integer programming, and stochastic satisfiability. We give a semantics for stochastic constraint programs, and propose a number...

  17. Famous face recognition, face matching, and extraversion.

    Science.gov (United States)

    Lander, Karen; Poyarekar, Siddhi

    2015-01-01

    It has been previously established that extraverts who are skilled at interpersonal interaction perform significantly better than introverts on a face-specific recognition memory task. In our experiment we further investigate the relationship between extraversion and face recognition, focusing on famous face recognition and face matching. Results indicate that more extraverted individuals perform significantly better on an upright famous face recognition task and show significantly larger face inversion effects. However, our results did not find an effect of extraversion on face matching or inverted famous face recognition.

  18. Face-to-face: Perceived personal relevance amplifies face processing.

    Science.gov (United States)

    Bublatzky, Florian; Pittig, Andre; Schupp, Harald T; Alpers, Georg W

    2017-05-01

    The human face conveys emotional and social information, but it is not well understood how these two aspects influence face perception. In order to model a group situation, two faces displaying happy, neutral or angry expressions were presented. Importantly, faces were either facing the observer, or they were presented in profile view directed towards, or looking away from each other. In Experiment 1 (n = 64), face pairs were rated regarding perceived relevance, wish-to-interact, and displayed interactivity, as well as valence and arousal. All variables revealed main effects of facial expression (emotional > neutral), face orientation (facing observer > towards > away) and interactions showed that evaluation of emotional faces strongly varies with their orientation. Experiment 2 (n = 33) examined the temporal dynamics of perceptual-attentional processing of these face constellations with event-related potentials. Processing of emotional and neutral faces differed significantly in N170 amplitudes, early posterior negativity (EPN), and sustained positive potentials. Importantly, selective emotional face processing varied as a function of face orientation, indicating early emotion-specific (N170, EPN) and late threat-specific effects (LPP, sustained positivity). Taken together, perceived personal relevance to the observer-conveyed by facial expression and face direction-amplifies emotional face processing within triadic group situations. © The Author (2017). Published by Oxford University Press.

  19. Reactive scheduling algorithm for multiple mould and die projects based on optimized resource flow constraints%基于优化资源流约束的模具多项目反应调度算法

    Institute of Scientific and Technical Information of China (English)

    张沙清; 陈新度; 陈庆新; 陈新

    2011-01-01

    This paper proposed a reactive scheduling algorithm based on optimized resource flow constraints, which was used to repair multiple mould and die projects baseline schedule that suffer from multiple tasks taking long time than planning during projects execution. Firstly, a baseline schedule minimizing weighted sum duration of projects was built with priority rules based particle swarm optimization and a resource flow network was built and optimized for the baseline schedule with heuristic algorithm. By combining critical chain technology and resource flow network, the baseline schedule was improved by setting proper time buffers. Then, a heuristic reactive scheduling model with the optimization object of minimizing the disruptions cost when tasks starting time changed during projects execution was constructed and priority rules based particle swarm optimization was used to solve it. Finally, the feasibility and reliability of the above reactive algorithm were analyzed by simulations and the results show that this algorithm could effectively solve dynamic scheduling problems for multiple mould and die projects with multiple tasks duration enlarging.%针对模具多项目执行过程中由于任务拖期而导致的调度计划变更,提出了一种基于优化的资源流约束的反应调度算法.首先利用基于优先规则的微粒群算法构建一个项目加权工期之和最小的初始调度计划,采用启发式算法建立并优化初始调度计划的资源流网络,并将关键链技术与资源流网络相结合,对初始调度计划进行合理的时间缓冲设置.然后建立了以调度计划扰动费用最小为优化目标的反应调度模型,并用基于优先规则的微粒群算法进行求解.最后,通过仿真计算分析了算法的可行性与可靠性,结果表明该反应调度算法在模具多项目动态调度中具有一定的应用价值.

  20. Lesões múltiplas de osteoma cutis na face: terapêutica minimamente invasiva em pacientes com sequela de acne - relato de casos Multiple injuries of osteoma skin in the face: therapeutical least invasive in patients with acne sequela - case report

    Directory of Open Access Journals (Sweden)

    Ian Göedert Leite Duarte

    2010-10-01

    Full Text Available Osteoma cutis é a formação óssea no interior da pele, podendo ser primária ou secundária. Única ou múltipla, de tamanhos variados e acometendo ambos os sexos, é uma lesão cutânea rara, de etiopatogenia e classificação ainda discutidas. Nosso objetivo foi relatar o diagnóstico e a terapêutica minimamente invasiva de lesões múltiplas de osteoma cutis na face em pacientes com sequelas de acne. Fizemos a retirada dos osteomas com agulhas BD 0,70 x 25 22G1, sem anestésicos tópicos ou injetáveis no local. As pequenas incisões foram deixadas expostas, com pomada cicatrizante. Obteve-se um excelente resultado estético em 15 dias.Osteoma cutis is a bone formation in the dermis can to be primary or secondary forms. Only, multiples, many forms, occurring on either sex, they are a rare cutaneous disease. The pathogenesis and classification remains unclear. Our objective was the diagnostic and small invasive surgery treatment of the osteoma cutis multiple of the face, in patients as a sequel of acne. To remove the osteoma we used needle BD 0,70x25 22G1, without anesthetic topic or inject able site. The small wounds were exposed with scarring balsam. We got an excellent esthetic result after 15 days.

  1. Individual differences in holistic processing predict face recognition ability.

    Science.gov (United States)

    Wang, Ruosi; Li, Jingguang; Fang, Huizhen; Tian, Moqian; Liu, Jia

    2012-02-01

    Why do some people recognize faces easily and others frequently make mistakes in recognizing faces? Classic behavioral work has shown that faces are processed in a distinctive holistic manner that is unlike the processing of objects. In the study reported here, we investigated whether individual differences in holistic face processing have a significant influence on face recognition. We found that the magnitude of face-specific recognition accuracy correlated with the extent to which participants processed faces holistically, as indexed by the composite-face effect and the whole-part effect. This association is due to face-specific processing in particular, not to a more general aspect of cognitive processing, such as general intelligence or global attention. This finding provides constraints on computational models of face recognition and may elucidate mechanisms underlying cognitive disorders, such as prosopagnosia and autism, that are associated with deficits in face recognition.

  2. Challenges facing production grids

    Energy Technology Data Exchange (ETDEWEB)

    Pordes, Ruth; /Fermilab

    2007-06-01

    Today's global communities of users expect quality of service from distributed Grid systems equivalent to that their local data centers. This must be coupled to ubiquitous access to the ensemble of processing and storage resources across multiple Grid infrastructures. We are still facing significant challenges in meeting these expectations, especially in the underlying security, a sustainable and successful economic model, and smoothing the boundaries between administrative and technical domains. Using the Open Science Grid as an example, I examine the status and challenges of Grids operating in production today.

  3. Multiple Constraints in Theories of Metaphor

    Science.gov (United States)

    Gibbs, Raymond W., Jr.

    2011-01-01

    Critics of conceptual metaphor theory (CMT) argue that metaphors are produced and understood as novel meaning creations, and often note that other factors may account for some of the ways people use and understand metaphors apart from entrenched metaphorical concepts, or conceptual metaphors. This article situates CMT within the multidisciplinary…

  4. 多约束条件下互联网骨干网路由器级拓扑生成方法%Router-level topology generation research for Internet backbone networks under multiple constraints

    Institute of Scientific and Technical Information of China (English)

    吴元立; 司光亚; 罗批

    2016-01-01

    互联网骨干网是网络流量的中枢传输系统,其路由器级拓扑结构对于网络抗毁性分析具有重要意义。由于难以获取互联网骨干网路由器级的真实拓扑,通过分析骨干网的形成因素,将地理位置、节点间联系强度、基础设施费用、鲁棒性等因素结合起来,提出一种多约束条件下的互联网骨干网路由器级拓扑生成方法。该方法既可以构造难以公开获取网络测量数据的骨干网,也可以用来生成某一骨干网的多种替身拓扑集。通过现实中的互联网骨干网作为实例,验证了方法的有效性。%The backbone network is the main part of the Internet traffic transfer system,and the router-level topology of backbone network is of great significance for the research on network survivability.Due to various reasons,it is difficult to get real Internet backbone router level topology.By analyzing the forming driving factors of backbone network,the geographical constraints,the exchanging strength of nodes, infrastructure cost and robustness,etc.were combined;the router-level topology generation method for Internet backbone networks under multiple constraints was proposed.The method can generate router level topology for network which cannot be inferred from publicly accessible measurement data,and can generate topology set that consists of realistic alternatives for a backbone network.Finally,the effectiveness of the method is verified by two real Internet backbone networks.

  5. Utility maximization under solvency constraints and unhedgeable risks

    NARCIS (Netherlands)

    T. Kleinow; A. Pelsser

    2008-01-01

    We consider the utility maximization problem for an investor who faces a solvency or risk constraint in addition to a budget constraint. The investor wishes to maximize her expected utility from terminal wealth subject to a bound on her expected solvency at maturity. We measure solvency using a solv

  6. The Soft Cumulative Constraint

    CERN Document Server

    Petit, Thierry

    2009-01-01

    This research report presents an extension of Cumulative of Choco constraint solver, which is useful to encode over-constrained cumulative problems. This new global constraint uses sweep and task interval violation-based algorithms.

  7. Composing constraint solvers

    NARCIS (Netherlands)

    Zoeteweij, P.

    2005-01-01

    Composing constraint solvers based on tree search and constraint propagation through generic iteration leads to efficient and flexible constraint solvers. This was demonstrated using OpenSolver, an abstract branch-and-propagate tree search engine that supports a wide range of relevant solver configu

  8. The Multiple Faces of Reflexive Research Designs

    Directory of Open Access Journals (Sweden)

    Karl H. Müller

    2015-10-01

    Full Text Available Reflexive research can be grouped into five clusters with circular relations between two elements x ↔ x, namely circular relations between observers, between scientific building blocks like concepts, theories or models, between systemic levels, between rules and rule systems or as circular relations or x ↔ y between these four components. By far the most important cluster is the second cluster which becomes reflexive through a re-entry operation RE into a scientific element x and which establishes its circular formation as x(x. Many of the research problems in these five clusters in reflexivity research are still unexplored and pose grand challenges for future research.

  9. The multiple faces of leukocyte interstitial migration

    Science.gov (United States)

    Lämmermann, Tim; Germain, Ronald N.

    2014-01-01

    Spatiotemporal control of leukocyte dynamics within tissues is critical for successful innate and adaptive immune responses. Homeostatic trafficking and coordinated infiltration into and within sites of inflammation and infection rely on signaling in response to extracellular cues that in turn controls a variety of intracellular protein networks regulating leukocyte motility, migration, chemotaxis, positioning, and cell–cell interaction. In contrast to mesenchymal cells, leukocytes migrate in an amoeboid fashion by rapid cycles of actin polymerization and actomyosin contraction, and their migration in tissues is generally referred to as low adhesive and nonproteolytic. The interplay of actin network expansion, contraction, and adhesion shapes the exact mode of amoeboid migration, and in this review, we explore how leukocyte subsets potentially harness the same basic biomechanical mechanisms in a cell-type-specific manner. Most of our detailed understanding of these processes derives from in vitro migration studies in three-dimensional gels and confined spaces that mimic geometrical aspects of physiological tissues. We summarize these in vitro results and then critically compare them to data from intravital imaging of leukocyte interstitial migration in mouse tissues. We outline the technical challenges of obtaining conclusive mechanistic results from intravital studies, discuss leukocyte migration strategies in vivo, and present examples of mode switching during physiological interstitial migration. These findings are also placed in the context of leukocyte migration defects in primary immunodeficiencies. This overview of both in vitro and in vivo studies highlights recent progress in understanding the molecular and biophysical mechanisms that shape robust leukocyte migration responses in physiologically complex and heterogeneous environments. PMID:24573488

  10. The Multiple Faces of Effective Grand Strategy

    Directory of Open Access Journals (Sweden)

    Bryan N. Groves

    2010-01-01

    Full Text Available Effective national leaders throughout history have deliberately developed grand strategies and successfully implemented them to attain their political goals, while also integrating and accomplishing economic, social, defense, and sometimes religious objectives. Not all leaders have been successful, however, as this process is immensely complex and can be adversely affected by the actions of other leaders around their region and the world. It bears examination, then, to determine what factors contribute to successful grand strategies and why many leaders fail to reach their stated ends. This article utilizes a historic case study approach and explores three key areas of grand strategy: universal principles, Clausewitzian approaches, and indirect approaches. I handle each separately and in distinct fashion, though some connective tissue does interlace across sections. Additionally, the unifying argument is that thoughtful, rational leaders, who weigh the costs and benefits associated with each course of action available to them, still must heed the truths embedded in these three sections to attain their objectives. Not doing so often leads to failure, unrealized goals, and a nation gone awry.

  11. Attractive faces temporally modulate visual attention

    Directory of Open Access Journals (Sweden)

    Koyo eNakamura

    2014-06-01

    Full Text Available Facial attractiveness is an important biological and social signal on social interaction. Recent research has demonstrated that an attractive face captures greater spatial attention than an unattractive face does. Little is known, however, about the temporal characteristics of visual attention for facial attractiveness. In this study, we investigated the temporal modulation of visual attention induced by facial attractiveness by using a rapid serial visual presentation (RSVP. Fourteen male faces and two female faces were successively presented for 160 ms respectively, and participants were asked to identify two female faces embedded among a series of multiple male distractor faces. Identification of a second female target (T2 was impaired when a first target (T1 was attractive compared to neutral or unattractive faces, at 320 ms SOA; identification was improved when T1 was attractive compared to unattractive faces at 640 ms SOA. These findings suggest that the spontaneous appraisal of facial attractiveness modulates temporal attention.

  12. On Testing Constraint Programs

    CERN Document Server

    Lazaar, Nadjib; Yahia, Lebbah

    2010-01-01

    The success of several constraint-based modeling languages such as OPL, ZINC, or COMET, appeals for better software engineering practices, particularly in the testing phase. This paper introduces a testing framework enabling automated test case generation for constraint programming. We propose a general framework of constraint program development which supposes that a first declarative and simple constraint model is available from the problem specifications analysis. Then, this model is refined using classical techniques such as constraint reformulation, surrogate and global constraint addition, or symmetry-breaking to form an improved constraint model that must be thoroughly tested before being used to address real-sized problems. We think that most of the faults are introduced in this refinement step and propose a process which takes the first declarative model as an oracle for detecting non-conformities. We derive practical test purposes from this process to generate automatically test data that exhibit no...

  13. Instructional constraints faced by learners with duchenne muscular ...

    African Journals Online (AJOL)

    Administrator

    case study of Joy Town Special Primary School, Thika, Kenya. ... birth, symptoms usually progresses slowly and include general weakness ... Dystrophy Association was formed in 1950 in the United States of America by parents whose children had muscular .... According to Gay (1973), the descriptive method of research.

  14. European cinema: face to face with Hollywood

    NARCIS (Netherlands)

    T. Elsaesser

    2005-01-01

    In the face of renewed competition from Hollywood since the early 1980s and the challenges posed to Europe's national cinemas by the fall of the Wall in 1989, independent filmmaking in Europe has begun to re-invent itself. European Cinema: Face to Face with Hollywood re-assesses the different debate

  15. Mapping Teacher-Faces

    Science.gov (United States)

    Thompson, Greg; Cook, Ian

    2013-01-01

    This paper uses Deleuze and Guattari's concept of faciality to analyse the teacher's face. According to Deleuze and Guattari, the teacher-face is a special type of face because it is an "overcoded" face produced in specific landscapes. This paper suggests four limit-faces for teacher faciality that actualise different mixes of significance and…

  16. Robust Face Image Matching under Illumination Variations

    Directory of Open Access Journals (Sweden)

    Yang Chyuan-Huei Thomas

    2004-01-01

    Full Text Available Face image matching is an essential step for face recognition and face verification. It is difficult to achieve robust face matching under various image acquisition conditions. In this paper, a novel face image matching algorithm robust against illumination variations is proposed. The proposed image matching algorithm is motivated by the characteristics of high image gradient along the face contours. We define a new consistency measure as the inner product between two normalized gradient vectors at the corresponding locations in two images. The normalized gradient is obtained by dividing the computed gradient vector by the corresponding locally maximal gradient magnitude. Then we compute the average consistency measures for all pairs of the corresponding face contour pixels to be the robust matching measure between two face images. To alleviate the problem due to shadow and intensity saturation, we introduce an intensity weighting function for each individual consistency measure to form a weighted average of the consistency measure. This robust consistency measure is further extended to integrate multiple face images of the same person captured under different illumination conditions, thus making our robust face matching algorithm. Experimental results of applying the proposed face image matching algorithm on some well-known face datasets are given in comparison with some existing face recognition methods. The results show that the proposed algorithm consistently outperforms other methods and achieves higher than 93% recognition rate with three reference images for different datasets under different lighting conditions.

  17. Photogrammetric Network for Evaluation of Human Faces for Face Reconstruction Purpose

    Science.gov (United States)

    Schrott, P.; Detrekői, Á.; Fekete, K.

    2012-08-01

    Facial reconstruction is the process of reconstructing the geometry of faces of persons from skeletal remains. A research group (BME Cooperation Research Center for Biomechanics) was formed representing several organisations to combine knowledgebases of different disciplines like anthropology, medical, mechanical, archaeological sciences etc. to computerize the face reconstruction process based on a large dataset of 3D face and skull models gathered from living persons: cranial data from CT scans and face models from photogrammetric evaluations. The BUTE Dept. of Photogrammetry and Geoinformatics works on the method and technology of the 3D data acquisition for the face models. In this paper we will present the research and results of the photogrammetric network design, the modelling to deal with visibility constraints, and the investigation of the developed basic photogrammetric configuration to specify the result characteristics to be expected using the device built for the photogrammetric face measurements.

  18. Constraints meet concurrency

    CERN Document Server

    Mauro, Jacopo

    2014-01-01

    This book describes the benefits that emerge when the fields of constraint programming and concurrency meet. On the one hand, constraints can be used in concurrency theory to increase the conciseness and the expressive power of concurrent languages from a pragmatic point of view. On the other hand, problems modeled by using constraints can be solved faster and more efficiently using a concurrent system. Both directions are explored providing two separate lines of development. Firstly the expressive power of a concurrent language is studied, namely Constraint Handling Rules, that supports constraints as a primitive construct. The features of this language which make it Turing powerful are shown. Then a framework is proposed to solve constraint problems that is intended to be deployed on a concurrent system. For the development of this framework the concurrent language Jolie following the Service Oriented paradigm is used. Based on this experience, an extension to Service Oriented Languages is also proposed in ...

  19. A survey of real face modeling methods

    Science.gov (United States)

    Liu, Xiaoyue; Dai, Yugang; He, Xiangzhen; Wan, Fucheng

    2017-09-01

    The face model has always been a research challenge in computer graphics, which involves the coordination of multiple organs in faces. This article explained two kinds of face modeling method which is based on the data driven and based on parameter control, analyzed its content and background, summarized their advantages and disadvantages, and concluded muscle model which is based on the anatomy of the principle has higher veracity and easy to drive.

  20. On Minimal Constraint Networks

    CERN Document Server

    Gottlob, Georg

    2011-01-01

    In a minimal binary constraint network, every tuple of a constraint relation can be extended to a solution. It was conjectured that computing a solution to such a network is NP complete. We prove this conjecture true and show that the problem remains NP hard even in case the total domain of all values that may appear in the constraint relations is bounded by a constant.

  1. Temporal Concurrent Constraint Programming

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Valencia Posso, Frank Dan

    2002-01-01

    The ntcc calculus is a model of non-deterministic temporal concurrent constraint programming. In this paper we study behavioral notions for this calculus. In the underlying computational model, concurrent constraint processes are executed in discrete time intervals. The behavioral notions studied...... reflect the reactive interactions between concurrent constraint processes and their environment, as well as internal interactions between individual processes. Relationships between the suggested notions are studied, and they are all proved to be decidable for a substantial fragment of the calculus...

  2. A PSO-Optimized Reciprocal Velocity Obstacles Algorithm for Navigation of Multiple Mobile Robots

    OpenAIRE

    Ziyad Allawi; Turki Abdalla

    2015-01-01

    In this paper, a new optimization method for the Reciprocal Velocity Obstacles (RVO) is proposed. It uses the well-known Particle Swarm Optimization (PSO) for navigation control of multiple mobile robots with kinematic constraints. The RVO is used for collision avoidance between the robots, while PSO is used to choose the best path for the robot maneuver to avoid colliding with other robots and to get to its goal faster. This method was applied on 24 mobile robots facing each other. Simulatio...

  3. Normal composite face effects in developmental prosopagnosia.

    Science.gov (United States)

    Biotti, Federica; Wu, Esther; Yang, Hua; Jiahui, Guo; Duchaine, Bradley; Cook, Richard

    2017-08-10

    Upright face perception is thought to involve holistic processing, whereby local features are integrated into a unified whole. Consistent with this view, the top half of one face appears to fuse perceptually with the bottom half of another, when aligned spatially and presented upright. This 'composite face effect' reveals a tendency to integrate information from disparate regions when faces are presented canonically. In recent years, the relationship between susceptibility to the composite effect and face recognition ability has received extensive attention both in participants with normal face recognition and participants with developmental prosopagnosia. Previous results suggest that individuals with developmental prosopagnosia may show reduced susceptibility to the effect suggestive of diminished holistic face processing. Here we describe two studies that examine whether developmental prosopagnosia is associated with reduced composite face effects. Despite using independent samples of developmental prosopagnosics and different composite procedures, we find no evidence for reduced composite face effects. The experiments yielded similar results; highly significant composite effects in both prosopagnosic groups that were similar in magnitude to the effects found in participants with normal face processing. The composite face effects exhibited by both samples and the controls were greatly diminished when stimulus arrangements were inverted. Our finding that the whole-face binding process indexed by the composite effect is intact in developmental prosopagnosia indicates that other factors are responsible for developmental prosopagnosia. These results are also inconsistent with suggestions that susceptibility to the composite face effect and face recognition ability are tightly linked. While the holistic process revealed by the composite face effect may be necessary for typical face perception, it is not sufficient; individual differences in face recognition ability

  4. Face activated neurodynamic cortical networks.

    Science.gov (United States)

    Susac, Ana; Ilmoniemi, Risto J; Ranken, Doug; Supek, Selma

    2011-05-01

    Previous neuroimaging studies have shown that complex visual stimuli, such as faces, activate multiple brain regions, yet little is known on the dynamics and complexity of the activated cortical networks during the entire measurable evoked response. In this study, we used simulated and face-evoked empirical MEG data from an oddball study to investigate the feasibility of accurate, efficient, and reliable spatio-temporal tracking of cortical pathways over prolonged time intervals. We applied a data-driven, semiautomated approach to spatio-temporal source localization with no prior assumptions on active cortical regions to explore non-invasively face-processing dynamics and their modulation by task. Simulations demonstrated that the use of multi-start downhill simplex and data-driven selections of time intervals submitted to the Calibrated Start Spatio-Temporal (CSST) algorithm resulted in improved accuracy of the source localization and the estimation of the onset of their activity. Locations and dynamics of the identified sources indicated a distributed cortical network involved in face processing whose complexity was task dependent. This MEG study provided the first non-invasive demonstration, agreeing with intracranial recordings, of an early onset of the activity in the fusiform face gyrus (FFG), and that frontal activation preceded parietal for responses elicited by target faces.

  5. Robust facial landmark detection based on initializing multiple poses

    Directory of Open Access Journals (Sweden)

    Xin Chai

    2016-10-01

    Full Text Available For robot systems, robust facial landmark detection is the first and critical step for face-based human identification and facial expression recognition. In recent years, the cascaded-regression-based method has achieved excellent performance in facial landmark detection. Nevertheless, it still has certain weakness, such as high sensitivity to the initialization. To address this problem, regression based on multiple initializations is established in a unified model; face shapes are then estimated independently according to these initializations. With a ranking strategy, the best estimate is selected as the final output. Moreover, a face shape model based on restricted Boltzmann machines is built as a constraint to improve the robustness of ranking. Experiments on three challenging datasets demonstrate the effectiveness of the proposed facial landmark detection method against state-of-the-art methods.

  6. Face-Lift

    Science.gov (United States)

    Tests and Procedures Face-lift By Mayo Clinic Staff A face-lift (rhytidectomy) is a cosmetic surgical procedure to improve the look of your face and neck. During a face-lift, facial soft tissues are lifted, excess skin is ...

  7. Theory of Constraints (TOC)

    DEFF Research Database (Denmark)

    Michelsen, Aage U.

    2004-01-01

    Tankegangen bag Theory of Constraints samt planlægningsprincippet Drum-Buffer-Rope. Endvidere skitse af The Thinking Process.......Tankegangen bag Theory of Constraints samt planlægningsprincippet Drum-Buffer-Rope. Endvidere skitse af The Thinking Process....

  8. Credit Constraints in Education

    Science.gov (United States)

    Lochner, Lance; Monge-Naranjo, Alexander

    2012-01-01

    We review studies of the impact of credit constraints on the accumulation of human capital. Evidence suggests that credit constraints have recently become important for schooling and other aspects of households' behavior. We highlight the importance of early childhood investments, as their response largely determines the impact of credit…

  9. Theory of Constraints (TOC)

    DEFF Research Database (Denmark)

    Michelsen, Aage U.

    2004-01-01

    Tankegangen bag Theory of Constraints samt planlægningsprincippet Drum-Buffer-Rope. Endvidere skitse af The Thinking Process.......Tankegangen bag Theory of Constraints samt planlægningsprincippet Drum-Buffer-Rope. Endvidere skitse af The Thinking Process....

  10. Temporal Concurrent Constraint Programming

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Palamidessi, Catuscia; Valencia, Frank Dan

    2002-01-01

    The ntcc calculus is a model of non-deterministic temporal concurrent constraint programming. In this paper we study behavioral notions for this calculus. In the underlying computational model, concurrent constraint processes are executed in discrete time intervals. The behavioral notions studied...

  11. Evaluating Distributed Timing Constraints

    DEFF Research Database (Denmark)

    Kristensen, C.H.; Drejer, N.

    1994-01-01

    In this paper we describe a solution to the problem of implementing time-optimal evaluation of timing constraints in distributed real-time systems.......In this paper we describe a solution to the problem of implementing time-optimal evaluation of timing constraints in distributed real-time systems....

  12. Ability or Finances as Constraints on Entrepreneurship?

    DEFF Research Database (Denmark)

    Andersen, Steffen; Meisner Nielsen, Kasper

    2012-01-01

    We use a natural experiment in Denmark to test the hypothesis that aspiring entrepreneurs face financial constraints because of low entrepreneurial quality. We identify 304 constrained entrepreneurs who start a business after receiving windfall wealth and examine the performance of these marginal...... entrepreneurs. We find that constrained entrepreneurs have significantly lower survival rates and lower profits when compared with a matched sample of unconstrained entrepreneurs. These results are consistent with the hypothesis that the marginal entrepreneur is of low quality....

  13. Ability or Finances as Constraints on Entrepreneurship?

    DEFF Research Database (Denmark)

    Andersen, Steffen; Meisner Nielsen, Kasper

    We use a natural experiment in Denmark to test the hypothesis that aspiring entrepreneurs face financial constraints because of low entrepreneurial quality. We identify 304 constrained entrepreneurs who start a business after receiving windfall wealth and examine the performance of these marginal...... entrepreneurs. We find that constrained entrepreneurs have significantly lower survival rates and lower profits when compared with a matched sample of unconstrained entrepreneurs. These results are consistent with the hypothesis that the marginal entrepreneur is of low quality....

  14. Decentralized Constraint Satisfaction

    CERN Document Server

    Duffy, K R; Leith, D J

    2011-01-01

    Constraint satisfaction problems (CSPs) lie at the heart of many modern industrial and commercial tasks. An important new collection of CSPs has recently been emerging that differ from classical problems in that they impose constraints on the class of algorithms that can be used to solve them. In computer network applications, these constraints arise as the variables within the CSP are located at physically distinct devices that cannot communicate. At each instant, every variable only knows if all its constraints are met or at least one is not. Consequently, the CSP's solution must be found using a decentralized approach. Existing algorithms for solving CSPs are either centralized or distributed, both of which violate these algorithmic constraints. In this article we present the first algorithm for solving CSPs that fulfills these new requirements. It is fully decentralized, making no use of a centralized controller or message-passing between variables. We prove that this algorithm converges with probability ...

  15. Constraints in Quantum Geometrodynamics

    CERN Document Server

    Gentle, A P; Kheyfets, A I; Miller, W A; Gentle, Adrian P.; George, Nathan D.; Kheyfets, Arkady; Miller, Warner A.

    2003-01-01

    We compare different treatments of the constraints in canonical quantum gravity. The standard approach on the superspace of 3-geometries treats the constraints as the sole carriers of the dynamic content of the theory, thus rendering the traditional dynamic equations obsolete. Quantization of the constraints in both the Dirac and ADM square root Hamiltonian approach lead to the well known problems of the description of time evolution. These problems of time are both of interpretational and technical nature. In contrast, the so-called geometrodynamic quantization procedure on the superspace of the true dynamic variables separates the issue of quantization from enforcing the constraints. The resulting theory takes into account the states that are off shell with respect to the constraints, and thus avoids the problems of time. Here, we develop, for the first time, the geometrodynamic quantization formalism in a general setting and show that it retains all essential features previously illustrated in the context ...

  16. Evaluating face trustworthiness: a model based approach.

    Science.gov (United States)

    Todorov, Alexander; Baron, Sean G; Oosterhof, Nikolaas N

    2008-06-01

    Judgments of trustworthiness from faces determine basic approach/avoidance responses and approximate the valence evaluation of faces that runs across multiple person judgments. Here, based on trustworthiness judgments and using a computer model for face representation, we built a model for representing face trustworthiness (study 1). Using this model, we generated novel faces with an increased range of trustworthiness and used these faces as stimuli in a functional Magnetic Resonance Imaging study (study 2). Although participants did not engage in explicit evaluation of the faces, the amygdala response changed as a function of face trustworthiness. An area in the right amygdala showed a negative linear response-as the untrustworthiness of faces increased so did the amygdala response. Areas in the left and right putamen, the latter area extended into the anterior insula, showed a similar negative linear response. The response in the left amygdala was quadratic--strongest for faces on both extremes of the trustworthiness dimension. The medial prefrontal cortex and precuneus also showed a quadratic response, but their response was strongest to faces in the middle range of the trustworthiness dimension.

  17. The hierarchical brain network for face recognition.

    Science.gov (United States)

    Zhen, Zonglei; Fang, Huizhen; Liu, Jia

    2013-01-01

    Numerous functional magnetic resonance imaging (fMRI) studies have identified multiple cortical regions that are involved in face processing in the human brain. However, few studies have characterized the face-processing network as a functioning whole. In this study, we used fMRI to identify face-selective regions in the entire brain and then explore the hierarchical structure of the face-processing network by analyzing functional connectivity among these regions. We identified twenty-five regions mainly in the occipital, temporal and frontal cortex that showed a reliable response selective to faces (versus objects) across participants and across scan sessions. Furthermore, these regions were clustered into three relatively independent sub-networks in a face-recognition task on the basis of the strength of functional connectivity among them. The functionality of the sub-networks likely corresponds to the recognition of individual identity, retrieval of semantic knowledge and representation of emotional information. Interestingly, when the task was switched to object recognition from face recognition, the functional connectivity between the inferior occipital gyrus and the rest of the face-selective regions were significantly reduced, suggesting that this region may serve as an entry node in the face-processing network. In sum, our study provides empirical evidence for cognitive and neural models of face recognition and helps elucidate the neural mechanisms underlying face recognition at the network level.

  18. Self-face recognition in social context.

    Science.gov (United States)

    Sugiura, Motoaki; Sassa, Yuko; Jeong, Hyeonjeong; Wakusawa, Keisuke; Horie, Kaoru; Sato, Shigeru; Kawashima, Ryuta

    2012-06-01

    The concept of "social self" is often described as a representation of the self-reflected in the eyes or minds of others. Although the appearance of one's own face has substantial social significance for humans, neuroimaging studies have failed to link self-face recognition and the likely neural substrate of the social self, the medial prefrontal cortex (MPFC). We assumed that the social self is recruited during self-face recognition under a rich social context where multiple other faces are available for comparison of social values. Using functional magnetic resonance imaging (fMRI), we examined the modulation of neural responses to the faces of the self and of a close friend in a social context. We identified an enhanced response in the ventral MPFC and right occipitoparietal sulcus in the social context specifically for the self-face. Neural response in the right lateral parietal and inferior temporal cortices, previously claimed as self-face-specific, was unaffected for the self-face but unexpectedly enhanced for the friend's face in the social context. Self-face-specific activation in the pars triangularis of the inferior frontal gyrus, and self-face-specific reduction of activation in the left middle temporal gyrus and the right supramarginal gyrus, replicating a previous finding, were not subject to such modulation. Our results thus demonstrated the recruitment of a social self during self-face recognition in the social context. At least three brain networks for self-face-specific activation may be dissociated by different patterns of response-modulation in the social context, suggesting multiple dynamic self-other representations in the human brain.

  19. Constraint-based reachability

    Directory of Open Access Journals (Sweden)

    Arnaud Gotlieb

    2013-02-01

    Full Text Available Iterative imperative programs can be considered as infinite-state systems computing over possibly unbounded domains. Studying reachability in these systems is challenging as it requires to deal with an infinite number of states with standard backward or forward exploration strategies. An approach that we call Constraint-based reachability, is proposed to address reachability problems by exploring program states using a constraint model of the whole program. The keypoint of the approach is to interpret imperative constructions such as conditionals, loops, array and memory manipulations with the fundamental notion of constraint over a computational domain. By combining constraint filtering and abstraction techniques, Constraint-based reachability is able to solve reachability problems which are usually outside the scope of backward or forward exploration strategies. This paper proposes an interpretation of classical filtering consistencies used in Constraint Programming as abstract domain computations, and shows how this approach can be used to produce a constraint solver that efficiently generates solutions for reachability problems that are unsolvable by other approaches.

  20. Solving geometric constraints with genetic simulated annealing algorithm

    Institute of Scientific and Technical Information of China (English)

    刘生礼; 唐敏; 董金祥

    2003-01-01

    This paper applies genetic simulated annealing algorithm (SAGA) to solving geometric constraint problems. This method makes full use of the advantages of SAGA and can handle under-/over- constraint problems naturally. It has advantages (due to its not being sensitive to the initial values) over the Newton-Raphson method, and its yielding of multiple solutions, is an advantage over other optimal methods for multi-solution constraint system. Our experiments have proved the robustness and efficiency of this method.

  1. Communication with Disturbance Constraints

    CERN Document Server

    Bandemer, Bernd

    2011-01-01

    The problem of communication with disturbance constraints is introduced. The rate-disturbance region is established for the single constraint case. The optimal encoding scheme turns out to be the same as the Han-Kobayashi scheme for the two user-pair interference channel. For communication with two disturbance constraints, a coding scheme and a corresponding inner bound for the deterministic case are presented. The results suggest a natural way to obtain a new inner bound on the capacity region of the interference channel with more than two user pairs.

  2. Panel workload assessment in US primary care: accounting for non-face-to-face panel management activities.

    Science.gov (United States)

    Arndt, Brian; Tuan, Wen-Jan; White, Jennifer; Schumacher, Jessica

    2014-01-01

    An understanding of primary care provider (PCP) workload is an important consideration in establishing optimal PCP panel size. However, no widely acceptable measure of PCP workload exists that incorporates the effort involved with both non-face-to-face patient care activities and face-to-face encounters. Accounting for this gap is critical given the increase in non-face-to-face PCP activities that has accompanied electronic health records (EHRs) (eg, electronic messaging). Our goal was to provide a comprehensive assessment of perceived PCP workload, accounting for aspects of both face-to-face and non-face-to-face encounters. Internal medicine, family medicine, and pediatric PCPs completed a self-administered survey about the perceived workload involved with face-to-face and non-face-to-face panel management activities as well as the perceived challenge associated with caring for patients with particular biomedical, demographic, and psychosocial characteristics (n = 185). Survey results were combined with EHR data at the individual patient and PCP service levels to assess PCP panel workload, accounting for face-to-face and non-face-to-face utilization. Of the multiple face-to-face and non-face-to-face activities associated with routine primary care, PCPs considered hospital admissions, obstetric care, hospital discharges, and new patient preventive health visits to be greater workload than non-face-to-face activities such as telephone calls, electronic communication, generating letters, and medication refills. Total workload within PCP panels at the individual patient level varied by overall health status, and the total workload of non-face-to-face panel management activities associated with routine primary care was greater than the total workload associated with face-to-face encounters regardless of health status. We used PCP survey results coupled with EHR data to assess PCP workload associated with both face-to-face as well as non-face-to-face panel management

  3. Impaired face recognition is associated with social inhibition.

    Science.gov (United States)

    Avery, Suzanne N; VanDerKlok, Ross M; Heckers, Stephan; Blackford, Jennifer U

    2016-02-28

    Face recognition is fundamental to successful social interaction. Individuals with deficits in face recognition are likely to have social functioning impairments that may lead to heightened risk for social anxiety. A critical component of social interaction is how quickly a face is learned during initial exposure to a new individual. Here, we used a novel Repeated Faces task to assess how quickly memory for faces is established. Face recognition was measured over multiple exposures in 52 young adults ranging from low to high in social inhibition, a core dimension of social anxiety. High social inhibition was associated with a smaller slope of change in recognition memory over repeated face exposure, indicating participants with higher social inhibition showed smaller improvements in recognition memory after seeing faces multiple times. We propose that impaired face learning is an important mechanism underlying social inhibition and may contribute to, or maintain, social anxiety.

  4. Optimization under Nonlinear Constraints

    OpenAIRE

    1982-01-01

    In this paper a timesaving method is proposed for maximizing likelihood functions when the parameter space is subject to nonlinear constraints, expressible as second order polynomials. The suggested approach is especially attractive when dealing with systems with many parameters.

  5. U.S./Japan burdensharing: constraints to increased Japanese contribution

    OpenAIRE

    Braker, Patrick J.

    1990-01-01

    Approved for public release; distribution is unlimited. This thesis explores issues relevant to U.S./Japan burdensharing. As U.S. defense expenditures are reduced in the 1990's, U.S. allies will be called upon to contribute a greater share to meet common security responsibilities. Japan's government faces a multitude of constraints to increasing defense expenditures placed upon them by the U.S., the Japanese public and Japan's Asian neighbors. Some of these constraints are affected sig...

  6. Multi-Constraint multi-processor Resource Allocation

    NARCIS (Netherlands)

    Behrouzian, A.R.B.; Goswami, D.; Basten, T.; Geilen, M.; Ara, H.A.

    2015-01-01

    This work proposes a Multi-Constraint Resource Allocation (MuCoRA) method for applications from multiple domains onto multi-processors. In particular, we address a mapping problem for multiple throughput-constrained streaming applications and multiple latency-constrained feedback control application

  7. About (above) a face - a face

    OpenAIRE

    2009-01-01

    This text intents to unfold some considerations regardind the perception of the image of the Lóri’s face, from the book Uma aprendizagem ou o livro dos prazeres, published by Clarice Lispector in 1969. For that, will be studied the politicians devices who involve the apprehension of the face as a qualifying of the subject and, at the same time, its relation with the lenguage.

  8. About (above a face - a face

    Directory of Open Access Journals (Sweden)

    Diego Cervelin

    2009-07-01

    Full Text Available This text intents to unfold some considerations regardind the perception of the image of the Lóri’s face, from the book Uma aprendizagem ou o livro dos prazeres, published by Clarice Lispector in 1969. For that, will be studied the politicians devices who involve the apprehension of the face as a qualifying of the subject and, at the same time, its relation with the lenguage.

  9. Implementation of Complex Projects Using Constraint Programming

    Directory of Open Access Journals (Sweden)

    Miodrag Strak

    2012-09-01

    Full Text Available During the implementation of the complex projects, all planned activities and resources must be taken into account. In general, it is necessary to assign the resources to the activities, but to also avoid simultaneous engagement of resources for multiple activities. In order to solve these problems, various techniques and methods are used. Mathematic and integer programming, genetic algorithms, simulated annealing, or taboo search are just some of the techniques used for solving this problem. Constraint programming comes from artificial intelligence i.e. papers from this area that occurred in 1960s and 1970s. Constraints exist in every segment of human environment. They represent a natural medium for expressing relations that exist in the physical world. Fulfilment of constraints is used in many different areas. Problems such as scheduling, allocations etc. are typical examples of constraints problems, where the basic concept of constraint programming can be applied. This paper considered implementation of the Bor Regional Development Project. Development of constraint programming was followed by the development of appropriate tools. B-Prolog was used in this paper. Many systems, including B-Prolog, enable interface with classic object-oriented languages, such as C++ or Java. One of the greatest advantages is the possibility of simple modelling, even for beginners in planning and implementation of the project.

  10. Computer Self-Efficacy, Anxiety, and Learning in Online versus Face to Face Medium

    Science.gov (United States)

    Hauser, Richard; Paul, Ravi; Bradley, John

    2012-01-01

    The purpose of this research is to examine the relationships between changes to computer self-efficacy (CSE) and computer anxiety and the impact on performance on computer-related tasks in both online and face-to-face mediums. While many studies have looked at these factors individually, relatively few have included multiple measures of these…

  11. Computer Self-Efficacy, Anxiety, and Learning in Online versus Face to Face Medium

    Science.gov (United States)

    Hauser, Richard; Paul, Ravi; Bradley, John

    2012-01-01

    The purpose of this research is to examine the relationships between changes to computer self-efficacy (CSE) and computer anxiety and the impact on performance on computer-related tasks in both online and face-to-face mediums. While many studies have looked at these factors individually, relatively few have included multiple measures of these…

  12. The composite face illusion.

    Science.gov (United States)

    Murphy, Jennifer; Gray, Katie L H; Cook, Richard

    2017-04-01

    Few findings in cognitive science have proved as influential as the composite face effect. When the top half of one face is aligned with the bottom half of another, and presented upright, the resulting composite arrangement induces a compelling percept of a novel facial configuration. Findings obtained using composite face procedures have contributed significantly to our understanding of holistic face processing, the detrimental effects of face inversion, the development of face perception, and aberrant face perception in clinical populations. Composite paradigms continue to advance our knowledge of face perception, as exemplified by their recent use for investigating the perceptual mechanisms underlying dynamic face processing. However, the paradigm has been the subject of intense scrutiny, particularly over the last decade, and there is a growing sense that the composite face illusion, whilst easy to illustrate, is deceptively difficult to measure and interpret. In this review, we provide a focussed overview of the existing composite face literature, and identify six priorities for future research. Addressing these gaps in our knowledge will aid the evaluation and refinement of theoretical accounts of the illusion.

  13. Utilizing the Zero-One Linear Programming Constraints to Draw Multiple Sets of Matched Samples from a Non-Treatment Population as Control Groups for the Quasi-Experimental Design

    Science.gov (United States)

    Li, Yuan H.; Yang, Yu N.; Tompkins, Leroy J.; Modarresi, Shahpar

    2005-01-01

    The statistical technique, "Zero-One Linear Programming," that has successfully been used to create multiple tests with similar characteristics (e.g., item difficulties, test information and test specifications) in the area of educational measurement, was deemed to be a suitable method for creating multiple sets of matched samples to be…

  14. The Intersection of Online and Face-to-Face Teaching: Implications for Virtual School Teacher Practice and Professional Development

    Science.gov (United States)

    Garrett Dikkers, Amy

    2015-01-01

    This mixed-method study reports perspectives of virtual school teachers on the impact of online teaching on their face-to-face practice. Data from a large-scale survey of teachers in the North Carolina Virtual Public School (n = 214), focus groups (n = 7), and interviews (n = 5) demonstrate multiple intersections between online and face-to-face…

  15. The photogrammetric inner constraints

    Science.gov (United States)

    Dermanis, Athanasios

    A derivation of the complete inner constraints, which are required for obtaining "free network" solutions in close-range photogrammetry, is presented. The inner constraints are derived analytically for the bundle method, by exploiting the fact that the rows of their coefficient matrix from a basis for the null subspace of the design matrix used in the linearized observation equations. The derivation is independent of any particular choice of rotational parameters and examples are given for three types of rotation angles used in photogrammetry, as well as for the Rodriguez elements. A convenient algorithm based on the use of the S-transformation is presented, for the computation of free solutions with either inner or partial inner constraints. This approach is finally compared with alternative approaches to free network solutions.

  16. Constraint algebra in bigravity

    Energy Technology Data Exchange (ETDEWEB)

    Soloviev, V. O., E-mail: Vladimir.Soloviev@ihep.ru [National Research Center Kurchatov Institute, Institute for High Energy Physics (Russian Federation)

    2015-07-15

    The number of degrees of freedom in bigravity theory is found for a potential of general form and also for the potential proposed by de Rham, Gabadadze, and Tolley (dRGT). This aim is pursued via constructing a Hamiltonian formalismand studying the Poisson algebra of constraints. A general potential leads to a theory featuring four first-class constraints generated by general covariance. The vanishing of the respective Hessian is a crucial property of the dRGT potential, and this leads to the appearance of two additional second-class constraints and, hence, to the exclusion of a superfluous degree of freedom—that is, the Boulware—Deser ghost. The use of a method that permits avoiding an explicit expression for the dRGT potential is a distinctive feature of the present study.

  17. Psychological constraints on egalitarianism

    DEFF Research Database (Denmark)

    Kasperbauer, Tyler Joshua

    2015-01-01

    Debates over egalitarianism for the most part are not concerned with constraints on achieving an egalitarian society, beyond discussions of the deficiencies of egalitarian theory itself. This paper looks beyond objections to egalitarianism as such and investigates the relevant psychological...... processes motivating people to resist various aspects of egalitarianism. I argue for two theses, one normative and one descriptive. The normative thesis holds that egalitarians must take psychological constraints into account when constructing egalitarian ideals. I draw from non-ideal theories in political...... philosophy, which aim to construct moral goals with current social and political constraints in mind, to argue that human psychology must be part of a non-ideal theory of egalitarianism. The descriptive thesis holds that the most fundamental psychological challenge to egalitarian ideals comes from what...

  18. Constraints as evolutionary systems

    CERN Document Server

    Rácz, István

    2016-01-01

    The constraint equations for smooth $[n+1]$-dimensional (with $n\\geq 3$) Riemannian or Lorentzian spaces satisfying the Einstein field equations are considered. It is shown, regardless of the signature of the primary space, that the constraints can be put into the form of an evolutionary system comprised either by a first order symmetric hyperbolic system and a parabolic equation or, alternatively, by a strongly hyperbolic system and a subsidiary algebraic relation. In both cases the (local) existence and uniqueness of solutions are also discussed.

  19. Constraint-based scheduling applying constraint programming to scheduling problems

    CERN Document Server

    Baptiste, Philippe; Nuijten, Wim

    2001-01-01

    Constraint Programming is a problem-solving paradigm that establishes a clear distinction between two pivotal aspects of a problem: (1) a precise definition of the constraints that define the problem to be solved and (2) the algorithms and heuristics enabling the selection of decisions to solve the problem. It is because of these capabilities that Constraint Programming is increasingly being employed as a problem-solving tool to solve scheduling problems. Hence the development of Constraint-Based Scheduling as a field of study. The aim of this book is to provide an overview of the most widely used Constraint-Based Scheduling techniques. Following the principles of Constraint Programming, the book consists of three distinct parts: The first chapter introduces the basic principles of Constraint Programming and provides a model of the constraints that are the most often encountered in scheduling problems. Chapters 2, 3, 4, and 5 are focused on the propagation of resource constraints, which usually are responsibl...

  20. Semantic information can facilitate covert face recognition in congenital prosopagnosia.

    Science.gov (United States)

    Rivolta, Davide; Schmalzl, Laura; Coltheart, Max; Palermo, Romina

    2010-11-01

    People with congenital prosopagnosia have never developed the ability to accurately recognize faces. This single case investigation systematically investigates covert and overt face recognition in "C.," a 69 year-old woman with congenital prosopagnosia. Specifically, we: (a) describe the first assessment of covert face recognition in congenital prosopagnosia using multiple tasks; (b) show that semantic information can contribute to covert recognition; and (c) provide a theoretical explanation for the mechanisms underlying covert face recognition.

  1. A randomized, multicentre study of directed daylight exposure times of 11/2 vs. 21/2 h in daylight-mediated photodynamic therapy with methyl aminolaevulinate in patients with multiple thin actinic keratoses of the face and scalp

    DEFF Research Database (Denmark)

    Wiegell, S.R.; Fabricius, S.; Philipsen, P.A.

    2011-01-01

    in a randomized multicentre study. Methods: One hundred and twenty patients with a total of 1572 thin AKs of the face and scalp were randomized to either 11/2- or 21/2-h exposure groups. After gentle lesion preparation and application of a sunscreen of sun protection factor 20, MAL was applied to the entire...

  2. Oracle ADF Faces cookbook

    CERN Document Server

    Gawish, Amr

    2014-01-01

    This is a cookbook that covers more than 80 different recipes to teach you about different aspects of Oracle ADF Faces. It follows a practical approach and covers how to build your components for reuse in different applications. This book will also help you in tuning the performance of your ADF Faces application. If you are an ADF developer who wants to harness the power of Oracle ADF Faces to create exceptional user interfaces and reactive applications, this book will provide you with the recipes needed to do just that. You will not need to be familiar with Oracle ADF Faces, but you should be

  3. Constraint Optimization Literature Review

    Science.gov (United States)

    2015-11-01

    COPs. 15. SUBJECT TERMS high-performance computing, mobile ad hoc network, optimization, constraint, satisfaction 16. SECURITY CLASSIFICATION OF: 17...France): INRA Editions; 1996. p. 111–150. Black PE. Branch-and-bound. US national institute of standards and technology dictionary of algorithms

  4. Optimization of practical trusses with constraints on eigenfrequencies, displacements, stresses, and buckling

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Nielsen, A.

    2004-01-01

    and the objective of the optimizations is minimum mass with constraints on (possibly multiple) eigenfrequencies, displacements, and stresses. For the case of stress constraints, we deal differently with tensile and compressive stresses, for which we control buckling on the element level. The stress constraints...

  5. Generalization of affective learning about faces to perceptually similar faces.

    Science.gov (United States)

    Verosky, Sara C; Todorov, Alexander

    2010-06-01

    Different individuals have different (and different-looking) significant others, friends, and foes. The objective of this study was to investigate whether these social face environments can shape individual face preferences. First, participants learned to associate faces with positive, neutral, or negative behaviors. Then, they evaluated morphs combining novel faces with the learned faces. The morphs (65% and 80% novel faces) were within the categorical boundary of the novel faces: They were perceived as those faces in a preliminary study. Moreover, a second preliminary study showed that following the learning, the morphs' categorization as similar to the learned faces was indistinguishable from the categorization of actual novel faces. Nevertheless, in the main experiment, participants evaluated morphs of "positive" faces more positively than morphs of "negative" faces. This learning generalization effect increased as a function of the similarity of the novel faces to the learned faces. The findings suggest that general learning mechanisms based on similarity can account for idiosyncratic face preferences.

  6. Eccrine cylindroma of the face and scalp

    Directory of Open Access Journals (Sweden)

    Indu Manicketh

    2016-01-01

    Full Text Available Cylindroma is a benign skin adnexal tumor of eccrine differentiation. Clinically, they are disfiguring lesions that can mimic a malignancy. Cylindromas can be single or multiple and commonly involve the scalp (turban tumor and face. Multiple cylindromas can have a syndromic association as seen in Brooke–Spiegler syndrome and familial cylindromatosis. We present a case of non familial cylindroma of the face that clinically mimicked a basal cell carcinoma. The histopathology was confirmatory. Herein we also highlight the utility of a simple and inexpensive histochemical stain Periodic Acid Schiff in supporting the diagnosis.

  7. A constraint algorithm for singular Lagrangians subjected to nonholonomic constraints

    Energy Technology Data Exchange (ETDEWEB)

    de Leon, M. [Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 123, 28006 Madrid (Spain); de Diego, D.M. [Departamento de Economia Aplicada Cuantitativa, Facultad de Ciencias Economicas y Empresariales, UNED, 28040 Madrid (Spain)

    1997-06-01

    We construct a constraint algorithm for singular Lagrangian systems subjected to nonholonomic constraints which generalizes that of Dirac for constrained Hamiltonian systems. {copyright} {ital 1997 American Institute of Physics.}

  8. Social judgments from faces.

    Science.gov (United States)

    Todorov, Alexander; Mende-Siedlecki, Peter; Dotsch, Ron

    2013-06-01

    People make rapid and consequential social judgments from minimal (non-emotional) facial cues. There has been rapid progress in identifying the perceptual basis of these judgments using data-driven, computational models. In contrast, our understanding of the neural underpinnings of these judgments is rather limited. Meta-analyses of neuroimaging studies find a wide range of seemingly inconsistent responses in the amygdala that co-vary with social judgments from faces. Guided by computational models of social judgments, these responses can be accounted by positing that the amygdala (and posterior face selective regions) tracks face typicality. Atypical faces, whether positively or negatively evaluated, elicit stronger responses in the amygdala. We conclude with the promise of data-driven methods for modeling neural responses to social judgments from faces.

  9. Effects of Credit Constraint on Productivity and Rural Household Income in China

    OpenAIRE

    Dong, Fengxia; Lu, Jing; Featherstone, Allen M.

    2010-01-01

    Chinese rural household has been always facing credit constraints. Few institutions lend loans to farmers because of financial risks. Farmers have to use usury or other informal sources to meet the financial needs for production. This credit constraint has been forcing farmers to deviate from optimal resource allocation and production arrangement. Consequently, it affects farmers’ income growth. Therefore, the objective of this study is to examine how credit constraint affects agricultural pr...

  10. Examplers based image fusion features for face recognition

    CERN Document Server

    James, Alex Pappachen

    2012-01-01

    Examplers of a face are formed from multiple gallery images of a person and are used in the process of classification of a test image. We incorporate such examplers in forming a biologically inspired local binary decisions on similarity based face recognition method. As opposed to single model approaches such as face averages the exampler based approach results in higher recognition accu- racies and stability. Using multiple training samples per person, the method shows the following recognition accuracies: 99.0% on AR, 99.5% on FERET, 99.5% on ORL, 99.3% on EYALE, 100.0% on YALE and 100.0% on CALTECH face databases. In addition to face recognition, the method also detects the natural variability in the face images which can find application in automatic tagging of face images.

  11. Efficient Multi-site Data Movement Using Constraint Programming for Data Hungry Science

    CERN Document Server

    Zerola, Michal; Barták, Roman; Šumbera, Michal

    2009-01-01

    For the past decade, HENP experiments have been heading towards a distributed computing model in an effort to concurrently process tasks over enormous data sets that have been increasing in size as a function of time. In order to optimize all available resources (geographically spread) and minimize the processing time, it is necessary to face also the question of efficient data transfers and placements. A key question is whether the time penalty for moving the data to the computational resources is worth the presumed gain. Onward to the truly distributed task scheduling we present the technique using a Constraint Programming (CP) approach. The CP technique schedules data transfers from multiple resources considering all available paths of diverse characteristic (capacity, sharing and storage) having minimum user's waiting time as an objective. We introduce a model for planning data transfers to a single destination (data transfer) as well as its extension for an optimal data set spreading strategy (data place...

  12. Dynamical Constraints on Exoplanets

    CERN Document Server

    Horner, Jonti; Tinney, Chris; Hinse, Tobias C; Marshall, Jonathan P

    2013-01-01

    Dynamical studies of new exoplanet systems are a critical component of the discovery and characterisation process. Such studies can provide firmer constraints on the parameters of the newly discovered planets, and may even reveal that the proposed planets do not stand up to dynamical scrutiny. Here, we demonstrate how dynamical studies can assist the characterisation of such systems through two examples: QS Virginis and HD 73526.

  13. The NCL natural constraint language

    CERN Document Server

    Zhou, Jianyang

    2012-01-01

    This book presents the Natural Constraint Language (NCL) language, a description language in conventional mathematical logic for modeling and solving constraint satisfaction problems. It uses illustrations and tutorials to detail NCL and its applications.

  14. Constraints on Relaxion Windows

    CERN Document Server

    Choi, Kiwoon

    2016-01-01

    We examine low energy phenomenology of the relaxion solution to the weak scale hierarchy problem. Assuming that the Hubble friction is responsible for the dissipation of relaxion energy, we identify the cosmological relaxion window which corresponds to the parameter region compatible with a given value of the acceptable number of inflationary $e$-foldings. We then discuss a variety of observational constraints on the relaxion window, while focusing on the case that the barrier potential to stabilize the relaxion is induced by new physics, rather than by low energy QCD dynamics. We find that majority of the parameter space with a relaxion mass $m_\\phi\\gtrsim 100$ eV or a relaxion decay constant $f\\lesssim 10^7$ GeV is excluded by existing constraints. There is an interesting small parameter region with $m_\\phi\\sim \\,0.2-1$ GeV and $f\\sim\\, {\\rm few}-10$ TeV, which is allowed by existing constraints, but can be probed soon by future beam dump experiment such as the SHiP experiment, or by improved EDM experiment...

  15. Handbook of Face Recognition

    CERN Document Server

    Li, Stan Z

    2011-01-01

    This highly anticipated new edition provides a comprehensive account of face recognition research and technology, spanning the full range of topics needed for designing operational face recognition systems. After a thorough introductory chapter, each of the following chapters focus on a specific topic, reviewing background information, up-to-date techniques, and recent results, as well as offering challenges and future directions. Features: fully updated, revised and expanded, covering the entire spectrum of concepts, methods, and algorithms for automated face detection and recognition systems

  16. Face Search at Scale.

    Science.gov (United States)

    Wang, Dayong; Otto, Charles; Jain, Anil K

    2016-06-20

    rsons of interest among the billions of shared photos on these websites. Despite significant progress in face recognition, searching a large collection of unconstrained face images remains a difficult problem. To address this challenge, we propose a face search system which combines a fast search procedure, coupled with a state-of-the-art commercial off the shelf (COTS) matcher, in a cascaded framework. Given a probe face, we first filter the large gallery of photos to find the top-k most similar faces using features learned by a convolutional neural network. The k retrieved candidates are re-ranked by combining similarities based on deep features and those output by the COTS matcher. We evaluate the proposed face search system on a gallery containing 80 million web-downloaded face images. Experimental results demonstrate that while the deep features perform worse than the COTS matcher on a mugshot dataset (93.7% vs. 98.6% TAR@FAR of 0.01%), fusing the deep features with the COTS matcher improves the overall performance (99.5% TAR@FAR of 0.01%). This shows that the learned deep features provide complementary information over representations used in state-of-the-art face matchers. On the unconstrained face image benchmarks, the performance of the learned deep features is competitive with reported accuracies. LFW database: 98.20% accuracy under the standard protocol and 88.03% TAR@FAR of 0.1% under the BLUFR protocol; IJB-A benchmark: 51.0% TAR@FAR of 0.1% (verification), rank 1 retrieval of 82.2% (closed-set search), 61.5% FNIR@FAR of 1% (open-set search). The proposed face search system offers an excellent trade-off between accuracy and scalability on galleries with millions of images. Additionally, in a face search experiment involving photos of the Tsarnaev brothers, convicted of the Boston Marathon bombing, the proposed cascade face search system could find the younger brother's (Dzhokhar Tsarnaev) photo at rank 1 in 1 second on a 5M gallery and at rank 8 in 7

  17. Parallel Handling of Integrity Constraints

    NARCIS (Netherlands)

    Grefen, P.W.P.J.; Flokstra, Jan; Apers, Peter M.G.

    1990-01-01

    Integrity constraints form an important part of a data model. Therefore, a complete integrity constraint handling subsystem is considered an important part of any modern DBMS. In implementing an integrity constraint handling subsystem, there are two major problem areas: providing enough functionalit

  18. A Coupled Hidden Markov Random Field Model for Simultaneous Face Clustering and Tracking in Videos

    KAUST Repository

    Wu, Baoyuan

    2016-10-25

    Face clustering and face tracking are two areas of active research in automatic facial video processing. They, however, have long been studied separately, despite the inherent link between them. In this paper, we propose to perform simultaneous face clustering and face tracking from real world videos. The motivation for the proposed research is that face clustering and face tracking can provide useful information and constraints to each other, thus can bootstrap and improve the performances of each other. To this end, we introduce a Coupled Hidden Markov Random Field (CHMRF) to simultaneously model face clustering, face tracking, and their interactions. We provide an effective algorithm based on constrained clustering and optimal tracking for the joint optimization of cluster labels and face tracking. We demonstrate significant improvements over state-of-the-art results in face clustering and tracking on several videos.

  19. Localized versus Locality-Preserving Subspace Projections for Face Recognition

    Directory of Open Access Journals (Sweden)

    Iulian B. Ciocoiu

    2007-05-01

    Full Text Available Three different localized representation methods and a manifold learning approach to face recognition are compared in terms of recognition accuracy. The techniques under investigation are (a local nonnegative matrix factorization (LNMF; (b independent component analysis (ICA; (c NMF with sparse constraints (NMFsc; (d locality-preserving projections (Laplacian faces. A systematic comparative analysis is conducted in terms of distance metric used, number of selected features, and sources of variability on AR and Olivetti face databases. Results indicate that the relative ranking of the methods is highly task-dependent, and the performances vary significantly upon the distance metric used.

  20. Localized versus Locality-Preserving Subspace Projections for Face Recognition

    Directory of Open Access Journals (Sweden)

    Costin HaritonN

    2007-01-01

    Full Text Available Three different localized representation methods and a manifold learning approach to face recognition are compared in terms of recognition accuracy. The techniques under investigation are (a local nonnegative matrix factorization (LNMF; (b independent component analysis (ICA; (c NMF with sparse constraints (NMFsc; (d locality-preserving projections (Laplacian faces. A systematic comparative analysis is conducted in terms of distance metric used, number of selected features, and sources of variability on AR and Olivetti face databases. Results indicate that the relative ranking of the methods is highly task-dependent, and the performances vary significantly upon the distance metric used.

  1. Constraint Logic Programming approach to protein structure prediction

    Directory of Open Access Journals (Sweden)

    Fogolari Federico

    2004-11-01

    Full Text Available Abstract Background The protein structure prediction problem is one of the most challenging problems in biological sciences. Many approaches have been proposed using database information and/or simplified protein models. The protein structure prediction problem can be cast in the form of an optimization problem. Notwithstanding its importance, the problem has very seldom been tackled by Constraint Logic Programming, a declarative programming paradigm suitable for solving combinatorial optimization problems. Results Constraint Logic Programming techniques have been applied to the protein structure prediction problem on the face-centered cube lattice model. Molecular dynamics techniques, endowed with the notion of constraint, have been also exploited. Even using a very simplified model, Constraint Logic Programming on the face-centered cube lattice model allowed us to obtain acceptable results for a few small proteins. As a test implementation their (known secondary structure and the presence of disulfide bridges are used as constraints. Simplified structures obtained in this way have been converted to all atom models with plausible structure. Results have been compared with a similar approach using a well-established technique as molecular dynamics. Conclusions The results obtained on small proteins show that Constraint Logic Programming techniques can be employed for studying protein simplified models, which can be converted into realistic all atom models. The advantage of Constraint Logic Programming over other, much more explored, methodologies, resides in the rapid software prototyping, in the easy way of encoding heuristics, and in exploiting all the advances made in this research area, e.g. in constraint propagation and its use for pruning the huge search space.

  2. Profitability and Constraints Analysis of Women Entrepreneurs in Lagos State, Nigeria

    Directory of Open Access Journals (Sweden)

    A.O. Otunaiya

    2013-01-01

    Full Text Available This research assessed the constraints limiting the success of women entrepreneurs in selected local government areas of Lagos State, Nigeria. A sample of 120 women entrepreneurs were selected from three Local Government Areas of Lagos State in a two-stage sampling procedure. The data collected were analyzed using descriptive statistics, constraint analysis, budgetary analysis and multiple regression analysis. The predominant primary occupation was found to be trading 45 with 92.5% of the women in their productive years. The finding also revealed that a vast majority (92.5% of the women entrepreneurs had formal education above primary level with 43.3% of them spent not less than 10 years in their business, which was presumed to benefit their enterprises. The women entrepreneurs faced certain constraints which affect their businesses, the highest ranked ones include; poor shop location (ranked 1st , lack of long term finance (ranked 2nd and competition from rivals (ranked 3rd among others. The women entrepreneurs earned 40 kobo on every 1 naira sale revenue. The multiple regression results revealed that main occupation, business membership strength, initial capital outlay and total variable cost had significant effect on the net income of the women. Policy options from the findings include: Increment in funds invested in the business enterprises of these women entrepreneurs alongside reduction in cost could boost the possible expansion of their enterprises; provision of psychological, moral and financial support from members of the family is needed for entrepreneurial development and Government should provide cheaper sources of credit to the women with little or no collateral to encourage their enterprises growth, self-reliance which are necessary ingredients for nation’s development.

  3. Weighted Attribute Fusion Model for Face Recognition

    CERN Document Server

    Sakthivel, S

    2010-01-01

    Recognizing a face based on its attributes is an easy task for a human to perform as it is a cognitive process. In recent years, Face Recognition is achieved with different kinds of facial features which were used separately or in a combined manner. Currently, Feature fusion methods and parallel methods are the facial features used and performed by integrating multiple feature sets at different levels. However, this integration and the combinational methods do not guarantee better result. Hence to achieve better results, the feature fusion model with multiple weighted facial attribute set is selected. For this feature model, face images from predefined data set has been taken from Olivetti Research Laboratory (ORL) and applied on different methods like Principal Component Analysis (PCA) based Eigen feature extraction technique, Discrete Cosine Transformation (DCT) based feature extraction technique, Histogram Based Feature Extraction technique and Simple Intensity based features. The extracted feature set obt...

  4. Toward a Social Psychophysics of Face Communication.

    Science.gov (United States)

    Jack, Rachael E; Schyns, Philippe G

    2017-01-03

    As a highly social species, humans are equipped with a powerful tool for social communication-the face. Although seemingly simple, the human face can elicit multiple social perceptions due to the rich variations of its movements, morphology, and complexion. Consequently, identifying precisely what face information elicits different social perceptions is a complex empirical challenge that has largely remained beyond the reach of traditional methods. In the past decade, the emerging field of social psychophysics has developed new methods to address this challenge, with the potential to transfer psychophysical laws of social perception to the digital economy via avatars and social robots. At this exciting juncture, it is timely to review these new methodological developments. In this article, we introduce and review the foundational methodological developments of social psychophysics, present work done in the past decade that has advanced understanding of the face as a tool for social communication, and discuss the major challenges that lie ahead.

  5. Multiple snapshot compressive beamforming

    DEFF Research Database (Denmark)

    Gerstoft, Peter; Xenaki, Angeliki; Mecklenbrauker, Christoph F.

    2015-01-01

    For sound fields observed on an array, compressive sensing (CS) reconstructs the multiple source signals at unknown directions-of-arrival (DOAs) using a sparsity constraint. The DOA estimation is posed as an underdetermined problem expressing the field at each sensor as a phase-lagged superposition...

  6. Tolerance for distorted faces: challenges to a configural processing account of familiar face recognition.

    Science.gov (United States)

    Sandford, Adam; Burton, A Mike

    2014-09-01

    Face recognition is widely held to rely on 'configural processing', an analysis of spatial relations between facial features. We present three experiments in which viewers were shown distorted faces, and asked to resize these to their correct shape. Based on configural theories appealing to metric distances between features, we reason that this should be an easier task for familiar than unfamiliar faces (whose subtle arrangements of features are unknown). In fact, participants were inaccurate at this task, making between 8% and 13% errors across experiments. Importantly, we observed no advantage for familiar faces: in one experiment participants were more accurate with unfamiliars, and in two experiments there was no difference. These findings were not due to general task difficulty - participants were able to resize blocks of colour to target shapes (squares) more accurately. We also found an advantage of familiarity for resizing other stimuli (brand logos). If configural processing does underlie face recognition, these results place constraints on the definition of 'configural'. Alternatively, familiar face recognition might rely on more complex criteria - based on tolerance to within-person variation rather than highly specific measurement.

  7. Constraints on muon-specific dark forces

    CERN Document Server

    Karshenboim, Savely G; Pospelov, Maxim

    2014-01-01

    The recent measurement of the Lamb shift in muonic hydrogen allows for the most precise extraction of the charge radius of the proton which is currently in conflict with other determinations based on $e-p$ scattering and hydrogen spectroscopy. This discrepancy could be the result of some new muon-specific force with O(1-100) MeV force carrier---in this paper we concentrate on vector mediators. Such an explanation faces challenges from the constraints imposed by the $g-2$ of the muon and electron as well as precision spectroscopy of muonic atoms. In this work we complement the family of constraints by calculating the contribution of hypothetical forces to the muonium hyperfine structure. We also compute the two-loop contribution to the electron parity violating amplitude due to a muon loop, which is sensitive to the muon axial-vector coupling. Overall, we find that the combination of low-energy constraints favors the mass of the mediator to be below 10 MeV, and that a certain degree of tuning is required betwe...

  8. Multicultural Students in Study Abroad: Their Interests, Their Issues, and Their Constraints

    Science.gov (United States)

    Brux, Jacqueline Murray; Fry, Blake

    2010-01-01

    Study abroad programs offer great potential to benefit students in an increasingly internationalized world and work place. Recently, a wide discussion among educators about the benefits of diversifying study abroad has developed, but students participating in study abroad may face many constraints, many of which are not faced by their majority…

  9. Comparison of face Recognition Algorithms on Dummy Faces

    Directory of Open Access Journals (Sweden)

    Aruni Singh

    2012-09-01

    Full Text Available In the age of rising crime face recognition is enormously important in the contexts of computer vision, psychology, surveillance, fraud detection, pattern recognition, neural network, content based video processing, etc. Face is a non intrusive strong biometrics for identification and hence criminals always try to hide their facial organs by different artificial means such as plastic surgery, disguise and dummy. The availability of a comprehensive face database is crucial to test the performance of these face recognition algorithms. However, while existing publicly-available face databases contain face images with a wide variety of poses, illumination, gestures and face occlusions but there is no dummy face database is available in public domain. The contributions of this research paper are: i Preparation of dummy face database of 110 subjects ii Comparison of some texture based, feature based and holistic face recognition algorithms on that dummy face database, iii Critical analysis of these types of algorithms on dummy face database.

  10. Is Face Distinctiveness Gender Based?

    Science.gov (United States)

    Baudouin, Jean-Yves; Gallay, Mathieu

    2006-01-01

    Two experiments were carried out to study the role of gender category in evaluations of face distinctiveness. In Experiment 1, participants had to evaluate the distinctiveness and the femininity-masculinity of real or artificial composite faces. The composite faces were created by blending either faces of the same gender (sexed composite faces,…

  11. Low dimensional representation of face space by face-selective inferior temporal neurons.

    Science.gov (United States)

    Salehi, Sina; Dehaqani, Mohammad-Reza A; Esteky, Hossein

    2017-05-01

    The representation of visual objects in primate brain is distributed and multiple neurons are involved in encoding each object. One way to understand the neural basis of object representation is to estimate the number of neural dimensions that are needed for veridical representation of object categories. In this study, the characteristics of the match between physical-shape and neural representational spaces in monkey inferior temporal (IT) cortex were evaluated. Specifically, we examined how the number of neural dimensions, stimulus behavioral saliency and stimulus category selectivity of neurons affected the correlation between shape and neural representational spaces in IT cortex. Single-unit recordings from monkey IT cortex revealed that there was a significant match between face space and its neural representation at lower neural dimensions, whereas the optimal match for the non-face objects was observed at higher neural dimensions. There was a statistically significant match between the face and neural spaces only in the face-selective neurons, whereas a significant match was observed for non-face objects in all neurons regardless of their category selectivity. Interestingly, the face neurons showed a higher match for the non-face objects than for the faces at higher neural dimensions. The optimal representation of face space in the responses of the face neurons was a low dimensional map that emerged early (~150 ms post-stimulus onset) and was followed by a high dimensional and relatively late (~300 ms) map for the non-face stimuli. These results support a multiplexing function for the face neurons in the representation of very similar shape spaces, but with different dimensionality and timing scales. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  12. PCA Based Rapid and Real Time Face Recognition Technique

    Directory of Open Access Journals (Sweden)

    T R Chandrashekar

    2013-12-01

    Full Text Available Economical and efficient that is used in various applications is face Biometric which has been a popular form biometric system. Face recognition system is being a topic of research for last few decades. Several techniques are proposed to improve the performance of face recognition system. Accuracy is tested against intensity, distance from camera, and pose variance. Multiple face recognition is another subtopic which is under research now a day. Speed at which the technique works is a parameter under consideration to evaluate a technique. As an example a support vector machine performs really well for face recognition but the computational efficiency degrades significantly with increase in number of classes. Eigen Face technique produces quality features for face recognition but the accuracy is proved to be comparatively less to many other techniques. With increase in use of core processors in personal computers and application demanding speed in processing and multiple face detection and recognition system (for example an entry detection system in shopping mall or an industry, demand for such systems are cumulative as there is a need for automated systems worldwide. In this paper we propose a novel system of face recognition developed with C# .Net that can detect multiple faces and can recognize the faces parallel by utilizing the system resources and the core processors. The system is built around Haar Cascade based face detection and PCA based face recognition system with C#.Net. Parallel library designed for .Net is used to aide to high speed detection and recognition of the real time faces. Analysis of the performance of the proposed technique with some of the conventional techniques reveals that the proposed technique is not only accurate, but also is fast in comparison to other techniques.

  13. Asteroseismic constraints for Gaia

    CERN Document Server

    Creevey, O L

    2012-01-01

    Distances from the Gaia mission will no doubt improve our understanding of stellar physics by providing an excellent constraint on the luminosity of the star. However, it is also clear that high precision stellar properties from, for example, asteroseismology, will also provide a needed input constraint in order to calibrate the methods that Gaia will use, e.g. stellar models or GSP_phot. For solar-like stars (F, G, K IV/V), asteroseismic data delivers at the least two very important quantities: (1) the average large frequency separation and (2) the frequency corresponding to the maximum of the modulated-amplitude spectrum nu_max. Both of these quantities are related directly to stellar parameters (radius and mass) and in particular their combination (gravity and density). We show how the precision in , nu_max, and atmospheric parameters T_eff and [Fe/H] affect the determination of gravity (log g) for a sample of well-known stars. We find that log g can be determined within less than 0.02 dex accuracy for ou...

  14. Design with Nonlinear Constraints

    KAUST Repository

    Tang, Chengcheng

    2015-12-10

    Most modern industrial and architectural designs need to satisfy the requirements of their targeted performance and respect the limitations of available fabrication technologies. At the same time, they should reflect the artistic considerations and personal taste of the designers, which cannot be simply formulated as optimization goals with single best solutions. This thesis aims at a general, flexible yet e cient computational framework for interactive creation, exploration and discovery of serviceable, constructible, and stylish designs. By formulating nonlinear engineering considerations as linear or quadratic expressions by introducing auxiliary variables, the constrained space could be e ciently accessed by the proposed algorithm Guided Projection, with the guidance of aesthetic formulations. The approach is introduced through applications in different scenarios, its effectiveness is demonstrated by examples that were difficult or even impossible to be computationally designed before. The first application is the design of meshes under both geometric and static constraints, including self-supporting polyhedral meshes that are not height fields. Then, with a formulation bridging mesh based and spline based representations, the application is extended to developable surfaces including origami with curved creases. Finally, general approaches to extend hard constraints and soft energies are discussed, followed by a concluding remark outlooking possible future studies.

  15. Incremental Nonnegative Matrix Factorization for Face Recognition

    Directory of Open Access Journals (Sweden)

    Wen-Sheng Chen

    2008-01-01

    Full Text Available Nonnegative matrix factorization (NMF is a promising approach for local feature extraction in face recognition tasks. However, there are two major drawbacks in almost all existing NMF-based methods. One shortcoming is that the computational cost is expensive for large matrix decomposition. The other is that it must conduct repetitive learning, when the training samples or classes are updated. To overcome these two limitations, this paper proposes a novel incremental nonnegative matrix factorization (INMF for face representation and recognition. The proposed INMF approach is based on a novel constraint criterion and our previous block strategy. It thus has some good properties, such as low computational complexity, sparse coefficient matrix. Also, the coefficient column vectors between different classes are orthogonal. In particular, it can be applied to incremental learning. Two face databases, namely FERET and CMU PIE face databases, are selected for evaluation. Compared with PCA and some state-of-the-art NMF-based methods, our INMF approach gives the best performance.

  16. Short-sale Constraints and Credit Runs

    DEFF Research Database (Denmark)

    Venter, Gyuri

    of prices to some agents who learn about the quality of an investment opportunity from market prices and have additional private information. Then I apply this observation when modeling a run on an investment bank by its short-term creditors, who are endowed with dispersed information and also learn from...... the price of an asset the bank holds. I show that short-selling constraints in the financial market lead to the revival of self-fulfilling beliefs about the beliefs and actions of others, and create multiple equilibria. In the equilibrium where agents rely more on public information (i.e., the price......), creditors with high private signals are more lenient to roll over debt, and a bank with lower asset quality remains solvent. This leads to higher allocative efficiency in the real economy. My result thus implies that the decrease in average informativeness due to short-sale constraints can be more than...

  17. Facing Aggression: Cues Differ for Female versus Male Faces

    Science.gov (United States)

    Geniole, Shawn N.; Keyes, Amanda E.; Mondloch, Catherine J.; Carré, Justin M.; McCormick, Cheryl M.

    2012-01-01

    The facial width-to-height ratio (face ratio), is a sexually dimorphic metric associated with actual aggression in men and with observers' judgements of aggression in male faces. Here, we sought to determine if observers' judgements of aggression were associated with the face ratio in female faces. In three studies, participants rated photographs of female and male faces on aggression, femininity, masculinity, attractiveness, and nurturing. In Studies 1 and 2, for female and male faces, judgements of aggression were associated with the face ratio even when other cues in the face related to masculinity were controlled statistically. Nevertheless, correlations between the face ratio and judgements of aggression were smaller for female than for male faces (F1,36 = 7.43, p = 0.01). In Study 1, there was no significant relationship between judgements of femininity and of aggression in female faces. In Study 2, the association between judgements of masculinity and aggression was weaker in female faces than for male faces in Study 1. The weaker association in female faces may be because aggression and masculinity are stereotypically male traits. Thus, in Study 3, observers rated faces on nurturing (a stereotypically female trait) and on femininity. Judgements of nurturing were associated with femininity (positively) and masculinity (negatively) ratings in both female and male faces. In summary, the perception of aggression differs in female versus male faces. The sex difference was not simply because aggression is a gendered construct; the relationships between masculinity/femininity and nurturing were similar for male and female faces even though nurturing is also a gendered construct. Masculinity and femininity ratings are not associated with aggression ratings nor with the face ratio for female faces. In contrast, all four variables are highly inter-correlated in male faces, likely because these cues in male faces serve as “honest signals”. PMID:22276184

  18. Consciousness of Social Face: the development and validation of a scale measuring desire to gain face versus fear of losing face.

    Science.gov (United States)

    Zhang, Xin-An; Cao, Qing; Grigoriou, Nicholas

    2011-01-01

    This article describes the development and validation of a scale that measures two distinct needs for individuals to manage their social "face". Scale development process resulted in an 11-item Consciousness of Social Face (CSF) scale made up of the following two correlated dimensions: desire to gain face and fear of losing face. The two-factor correlated structure of CSF scale was stable across multiple samples of both students and non-students subjects. The construct validity of CSF scale, including convergent validity, discriminant validity, and criterion-related validity was also demonstrated by examining relationships with other personality or demographical variables.

  19. Why Are Faces Denser in the Visual Experiences of Younger than Older Infants?

    Science.gov (United States)

    Jayaraman, Swapnaa; Fausey, Caitlin M.; Smith, Linda B.

    2017-01-01

    Recent evidence from studies using head cameras suggests that the frequency of faces directly in front of infants "declines" over the first year and a half of life, a result that has implications for the development of and evolutionary constraints on face processing. Two experiments tested 2 opposing hypotheses about this observed…

  20. Facing Sound - Voicing Art

    DEFF Research Database (Denmark)

    Lønstrup, Ansa

    2013-01-01

    This article is based on examples of contemporary audiovisual art, with a special focus on the Tony Oursler exhibition Face to Face at Aarhus Art Museum ARoS in Denmark in March-July 2012. My investigation involves a combination of qualitative interviews with visitors, observations of the audienc......´s interactions with the exhibition and the artwork in the museum space and short analyses of individual works of art based on reception aesthetics and phenomenology and inspired by newer writings on sound, voice and listening....

  1. Multiple Steady-state Solutions of PMSG Under Different Orientation Constraints%不同定向约束下直驱永磁同步风电机组多稳态解探讨

    Institute of Scientific and Technical Information of China (English)

    李生虎; 朱婷涵; 华玉婷

    2014-01-01

    In view of the need of a boundary condition to obtain the unique solution for the steady-state constraints of permanent magnet synchronous generators (PMSGs) that are a set of indeterminate equations with the reactive power output of the machine-side converter unfixed,steady-state solutions based on the stator current/voltage orientations are proposed.Because of inconsistency with the reactive power balance of the machine-side-converter,the solutions under two orientations are different. Further consideration of the power dispatch by adj usting the rotor speed or the pitch angle,steady-state solutions to PMSG are proposed.The numerical results show that:(1) the stator current orientation yields less active loss and higher efficiency,but absorbs more reactive power;(2)with increased wind speed,the PMSG absorbs more reactive power,the efficiency decreases with stator current orientation,but increases with stator voltage orientation;(3) active power dispatch may be realized by changing the rotor speed or the pitch angle,while the efficiency is different,and adj usting the pitch angle yields better convergence than adj usting the rotor speed.%针对直驱永磁同步发电机(PMSG)机侧变流器无功功率未知时,PMSG 稳态约束为不定方程组,需要补充边界条件才能得到唯一解的问题,文中建立了基于定子电流或定子电压定向约束的稳态求解算法。发现由于定向约束不能反映机侧无功平衡,两种定向下计算结果不一致。进一步考虑有功调度,在两种定向约束下分别采用转速调节或桨距角调节,建立 PMSG 稳态解算法。计算结果证实:定子电流定向时发电机有功损耗更小,机电能量转换效率更高,但是吸收无功功率更多;随风速增加,吸收无功功率增加,定子电流定向时发电机能量转换效率下降,定子电压定向时效率增加;转速偏离最优转速或增加桨距角,都可实现对PMSG的有功调度,但机电能量转换效率

  2. Generating virtual training samples for sparse representation of face images and face recognition

    Science.gov (United States)

    Du, Yong; Wang, Yu

    2016-03-01

    There are many challenges in face recognition. In real-world scenes, images of the same face vary with changing illuminations, different expressions and poses, multiform ornaments, or even altered mental status. Limited available training samples cannot convey these possible changes in the training phase sufficiently, and this has become one of the restrictions to improve the face recognition accuracy. In this article, we view the multiplication of two images of the face as a virtual face image to expand the training set and devise a representation-based method to perform face recognition. The generated virtual samples really reflect some possible appearance and pose variations of the face. By multiplying a training sample with another sample from the same subject, we can strengthen the facial contour feature and greatly suppress the noise. Thus, more human essential information is retained. Also, uncertainty of the training data is simultaneously reduced with the increase of the training samples, which is beneficial for the training phase. The devised representation-based classifier uses both the original and new generated samples to perform the classification. In the classification phase, we first determine K nearest training samples for the current test sample by calculating the Euclidean distances between the test sample and training samples. Then, a linear combination of these selected training samples is used to represent the test sample, and the representation result is used to classify the test sample. The experimental results show that the proposed method outperforms some state-of-the-art face recognition methods.

  3. Review on Matching Infrared Face Images to Optical Face Images using LBP

    Directory of Open Access Journals (Sweden)

    Kamakhaya Argulewar

    2014-12-01

    Full Text Available In biometric research and many security areas, it is very difficult task to match the images which is captured by different devices. Large gap exist between them because they relates with different classes. Matching optical face images to infrared face images is one of the difficult task in face biometric. Large difference exists between infrared and optical face images because they belong to multiple classes. Converting the samples of multimodality into common feature space is the main objective of this project. Different class of images is relating by coordinating separate feature for classes .It is mainly used in heterogeneous face recognition. The new method has been developing for identification of heterogeneous face identification. Training set contains the images from different modalities. Initially the infrared image is preprocessed by applying Gaussian filter, difference of Gaussian and CSDN filters are apply on infrared face image. After preprocessing next step to extracting the feature by using LBP(local binary pattern feature extraction then relevance machine classifier is used to identify the best matching optical image from the corresponding infrared images from the optical images dataset. By processing this technique our system efficiently match the infrared and optical face images.

  4. Rewriting Constraint Models with Metamodels

    CERN Document Server

    Chenouard, Raphael; Soto, Ricardo

    2010-01-01

    An important challenge in constraint programming is to rewrite constraint models into executable programs calculat- ing the solutions. This phase of constraint processing may require translations between constraint programming lan- guages, transformations of constraint representations, model optimizations, and tuning of solving strategies. In this paper, we introduce a pivot metamodel describing the common fea- tures of constraint models including different kinds of con- straints, statements like conditionals and loops, and other first-class elements like object classes and predicates. This metamodel is general enough to cope with the constructions of many languages, from object-oriented modeling languages to logic languages, but it is independent from them. The rewriting operations manipulate metamodel instances apart from languages. As a consequence, the rewriting operations apply whatever languages are selected and they are able to manage model semantic information. A bridge is created between the metamode...

  5. Constraint Propagation as Information Maximization

    CERN Document Server

    Abdallah, A Nait

    2012-01-01

    Dana Scott used the partial order among partial functions for his mathematical model of recursively defined functions. He interpreted the partial order as one of information content. In this paper we elaborate on Scott's suggestion of regarding computation as a process of information maximization by applying it to the solution of constraint satisfaction problems. Here the method of constraint propagation can be interpreted as decreasing uncertainty about the solution -- that is, as gain in information about the solution. As illustrative example we choose numerical constraint satisfaction problems to be solved by interval constraints. To facilitate this approach to constraint solving we formulate constraint satisfaction problems as formulas in predicate logic. This necessitates extending the usual semantics for predicate logic so that meaning is assigned not only to sentences but also to formulas with free variables.

  6. Efficient Searching with Linear Constraints

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Arge, Lars Allan; Erickson, Jeff

    2000-01-01

    We show how to preprocess a set S of points in d into an external memory data structure that efficiently supports linear-constraint queries. Each query is in the form of a linear constraint xd a0+∑d−1i=1 aixi; the data structure must report all the points of S that satisfy the constraint. This pr......We show how to preprocess a set S of points in d into an external memory data structure that efficiently supports linear-constraint queries. Each query is in the form of a linear constraint xd a0+∑d−1i=1 aixi; the data structure must report all the points of S that satisfy the constraint...

  7. Conjunction Faces Alter Confidence-Accuracy Relations for Old Faces

    Science.gov (United States)

    Reinitz, Mark Tippens; Loftus, Geoffrey R.

    2017-01-01

    The authors used a state-trace methodology to investigate the informational dimensions used to recognize old and conjunction faces (made by combining parts of separately studied faces). Participants in 3 experiments saw faces presented for 1 s each. They then received a recognition test; faces were presented for varying brief durations and…

  8. Pedagogical Characteristics of Online and Face-to-Face Classes

    Science.gov (United States)

    Wuensch, Karl; Aziz, Shahnaz; Ozan, Erol; Kishore, Masao; Tabrizi, M. H. Nassehzadeh

    2008-01-01

    Currently, many students have had experience with both face-to-face and online classes. We asked such students at 46 different universities in the United States to evaluate the pedagogical characteristics of their most recently completed face-to-face class and their most recently completed online class. The results show that students rate online…

  9. Bayesian Face Recognition and Perceptual Narrowing in Face-Space

    Science.gov (United States)

    Balas, Benjamin

    2012-01-01

    During the first year of life, infants' face recognition abilities are subject to "perceptual narrowing", the end result of which is that observers lose the ability to distinguish previously discriminable faces (e.g. other-race faces) from one another. Perceptual narrowing has been reported for faces of different species and different races, in…

  10. Constraints On Cosmic Dynamics

    CERN Document Server

    Mbonye, M R

    2003-01-01

    Observationally, the universe appears virtually critical. Yet, there is no simple explanation for this state. In this article we advance and explore the premise that the dynamics of the universe always seeks equilibrium conditions. Vacuum-induced cosmic accelerations lead to creation of matter-energy modes at the expense of vacuum energy. Because they gravitate, such modes constitute inertia against cosmic acceleration. On the other extreme, the would-be ultimate phase of local gravitational collapse is checked by a phase transition in the collapsing matter fields leading to a de Sitter-like fluid deep inside the black hole horizon, and at the expense of the collapsing matter fields. As a result, the universe succumbs to neither vacuum-induced run-away accelerations nor to gravitationally induced spacetime curvature singularities. Cosmic dynamics is self-regulating. We discuss the physical basis for these constraints and the implications, pointing out how the framework relates and helps resolve standing puzzl...

  11. Constraints on Spontaneous Entrainment

    Directory of Open Access Journals (Sweden)

    Richardson Michael J.

    2011-12-01

    Full Text Available Past research has revealed that a person's rhythmic limb movements become spontaneously entrained to an environmental rhythm if a. visual information about the environmental rhythm is available and b. its frequency of the environmental rhythm is near that of the person's movements. Further, this research has demonstrated that if the eyes track the environmental stimulus, the spontaneous entrainment to the environmental rhythm is strengthened. Experiments were performed to investigate two hypotheses that could explain this eye-tracking enhancement of spontaneous entrainment. One hypothesis is that eye tracking allows for the pick up of important coordinative information at the turn-around points of a movement trajectory. Another hypothesis is that the limb movements entrain to the moving eyes through a neuromotor synergy linking the eyes and limb. Results of these experiments will help delineate the informational and dynamical constraints that can impact the acquisition of skilled actions.

  12. Constraint-Based Categorial Grammar

    CERN Document Server

    Bouma, G; Bouma, Gosse; Noord, Gertjan van

    1994-01-01

    We propose a generalization of Categorial Grammar in which lexical categories are defined by means of recursive constraints. In particular, the introduction of relational constraints allows one to capture the effects of (recursive) lexical rules in a computationally attractive manner. We illustrate the linguistic merits of the new approach by showing how it accounts for the syntax of Dutch cross-serial dependencies and the position and scope of adjuncts in such constructions. Delayed evaluation is used to process grammars containing recursive constraints.

  13. A PSO-Optimized Reciprocal Velocity Obstacles Algorithm for Navigation of Multiple Mobile Robots

    Directory of Open Access Journals (Sweden)

    Ziyad Allawi

    2015-03-01

    Full Text Available In this paper, a new optimization method for the Reciprocal Velocity Obstacles (RVO is proposed. It uses the well-known Particle Swarm Optimization (PSO for navigation control of multiple mobile robots with kinematic constraints. The RVO is used for collision avoidance between the robots, while PSO is used to choose the best path for the robot maneuver to avoid colliding with other robots and to get to its goal faster. This method was applied on 24 mobile robots facing each other. Simulation results have shown that this method outperforms the ordinary RVO when the path is heuristically chosen.

  14. Causes and consequences of failed adaptation to biological invasions: the role of ecological constraints.

    Science.gov (United States)

    Lau, Jennifer A; terHorst, Casey P

    2015-05-01

    Biological invasions are a major challenge to native communities and have the potential to exert strong selection on native populations. As a result, native taxa may adapt to the presence of invaders through increased competitive ability, increased antipredator defences or altered morphologies that may limit encounters with toxic prey. Yet, in some cases, species may fail to adapt to biological invasions. Many challenges to adaptation arise because biological invasions occur in complex species-rich communities in spatially and temporally variable environments. Here, we review these 'ecological' constraints on adaptation, focusing on the complications that arise from the need to simultaneously adapt to multiple biotic agents and from temporal and spatial variation in both selection and demography. Throughout, we illustrate cases where these constraints might be especially important in native populations faced with biological invasions. Our goal was to highlight additional complexities empiricists should consider when studying adaptation to biological invasions and to begin to identify conditions when adaptation may fail to be an effective response to invasion. © 2015 John Wiley & Sons Ltd.

  15. A Probabilistic Model for Face Transformation with Application to Person Identification

    Directory of Open Access Journals (Sweden)

    Rose Kenneth

    2004-01-01

    Full Text Available A novel approach for content-based image retrieval and its specialization to face recognition are described. While most face recognition techniques aim at modeling faces, our goal is to model the transformation between face images of the same person. As a global face transformation may be too complex to be modeled directly, it is approximated by a collection of local transformations with a constraint that imposes consistency between neighboring transformations. Local transformations and neighborhood constraints are embedded within a probabilistic framework using two-dimensional hidden Markov models (2D HMMs. We further introduce a new efficient technique, called turbo-HMM (T-HMM for approximating intractable 2D HMMs. Experimental results on a face identification task show that our novel approach compares favorably to the popular eigenfaces and fisherfaces algorithms.

  16. Real Time Face Quality Assessment for Face Log Generation

    DEFF Research Database (Denmark)

    Kamal, Nasrollahi; Moeslund, Thomas B.

    2009-01-01

    Summarizing a long surveillance video to just a few best quality face images of each subject, a face-log, is of great importance in surveillance systems. Face quality assessment is the back-bone for face log generation and improving the quality assessment makes the face logs more reliable....... Developing a real time face quality assessment system using the most important facial features and employing it for face logs generation are the concerns of this paper. Extensive tests using four databases are carried out to validate the usability of the system....

  17. Cluster-based distributed face tracking in camera networks.

    Science.gov (United States)

    Yoder, Josiah; Medeiros, Henry; Park, Johnny; Kak, Avinash C

    2010-10-01

    In this paper, we present a distributed multicamera face tracking system suitable for large wired camera networks. Unlike previous multicamera face tracking systems, our system does not require a central server to coordinate the entire tracking effort. Instead, an efficient camera clustering protocol is used to dynamically form groups of cameras for in-network tracking of individual faces. The clustering protocol includes cluster propagation mechanisms that allow the computational load of face tracking to be transferred to different cameras as the target objects move. Furthermore, the dynamic election of cluster leaders provides robustness against system failures. Our experimental results show that our cluster-based distributed face tracker is capable of accurately tracking multiple faces in real-time. The overall performance of the distributed system is comparable to that of a centralized face tracker, while presenting the advantages of scalability and robustness.

  18. Face recognition system and method using face pattern words and face pattern bytes

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yufeng

    2014-12-23

    The present invention provides a novel system and method for identifying individuals and for face recognition utilizing facial features for face identification. The system and method of the invention comprise creating facial features or face patterns called face pattern words and face pattern bytes for face identification. The invention also provides for pattern recognitions for identification other than face recognition. The invention further provides a means for identifying individuals based on visible and/or thermal images of those individuals by utilizing computer software implemented by instructions on a computer or computer system and a computer readable medium containing instructions on a computer system for face recognition and identification.

  19. Two Faces of Japan.

    Science.gov (United States)

    Beasley, Conger, Jr.

    1992-01-01

    Discusses the inconsistency between Japanese exploitation of world natural resources and gestures to provide leadership in ecologically innovative technology. Explores Japanese culture, power structure, population trends, environmental ethics, industrialism, and international business practices as they relate to the philosophical face of…

  20. Facing Up to Death

    Science.gov (United States)

    Ross, Elizabeth Kubler

    1972-01-01

    Doctor urges that Americans accept death as a part of life and suggests ways of helping dying patients and their families face reality calmly, with peace. Dying children and their siblings, as well as children's feelings about relatives' deaths, are also discussed. (PD)

  1. Autonomous Face Segmentation

    Science.gov (United States)

    1992-09-01

    and Rhea Diamond. "From Piecemeal to Configurational Repre- sentation of Faces," Science, 195:312-314 (Jan 1977). 3. Damasio , Antonio R...34Prosopagnosia," Trends in Neuroscience, 8:132-135 (1985). 4. Damasio , Antonio R. and others. "Prosopagnosia: Anatomic Basis and Behav- ioral Mechanisms

  2. PrimeFaces blueprints

    CERN Document Server

    Jonna, Sudheer

    2014-01-01

    If you are a Java developer with experience of frontend UI development, and want to take the plunge to develop stunning UI applications with the most popular JSF framework, PrimeFaces, then this book is for you. For those with entrepreneurial aspirations, this book will provide valuable insights into how to utilize successful business models.

  3. Facing Up to Death

    Science.gov (United States)

    Ross, Elizabeth Kubler

    1972-01-01

    Doctor urges that Americans accept death as a part of life and suggests ways of helping dying patients and their families face reality calmly, with peace. Dying children and their siblings, as well as children's feelings about relatives' deaths, are also discussed. (PD)

  4. Age-Dependent Face Detection and Face Categorization Performance

    OpenAIRE

    Claus-Christian Carbon; Martina Grüter; Thomas Grüter

    2013-01-01

    Empirical studies on the development of face processing skills with age show inconsistent patterns concerning qualitative vs. quantitative changes over time or the age range for peak cognitive performance. In the present study, we tested the proficiency in face detection and face categorization with a large sample of participants (N = 312; age range: 2-88 yrs). As test objects, we used so-called Mooney faces, two-tone (black and white) images of faces lacking critical information of a local, ...

  5. Real-time face swapping as a tool for understanding infant self-recognition

    CERN Document Server

    Nguyen, Sao Mai; Asada, Minoru

    2011-01-01

    To study the preference of infants for contingency of movements and familiarity of faces during self-recognition task, we built, as an accurate and instantaneous imitator, a real-time face- swapper for videos. We present a non-constraint face-swapper based on 3D visual tracking that achieves real-time performance through parallel computing. Our imitator system is par- ticularly suited for experiments involving children with Autistic Spectrum Disorder who are often strongly disturbed by the constraints of other methods.

  6. Comparing Student Assessments and Perceptions of Online and Face-to-Face Versions of an Introductory Linguistics Course

    Science.gov (United States)

    Johnson, David; Palmer, Chris C.

    2015-01-01

    This article examines the issue of whether linguistics is better suited for a face-to-face (F2F) environment than an online teaching environment. Specifically, it examines assessment scores and student perceptions of the effectiveness of an introductory linguistics course at an undergraduate state university that has been taught multiple times in…

  7. Multiple provenance of rift sediments in the composite basin-mountain system: Constraints from detrital zircon U-Pb geochronology and heavy minerals of the early Eocene Jianghan Basin, central China

    Science.gov (United States)

    Wu, Lulu; Mei, Lianfu; Liu, Yunsheng; Luo, Jin; Min, Caizheng; Lu, Shengli; Li, Minghua; Guo, Libin

    2017-03-01

    Zircon U-Pb geochronology and heavy minerals are used in combination to provide valuable insights into the provenance of the early Eocene Jianghan Basin, central China. Five samples for zircon U-Pb dating and eighty-five samples for heavy mineral analysis were collected from drill cores or cuttings of the Xingouzui Formation. Most analyzed zircons are of magmatic origin, with oscillatory zoning. Detrital zircons from sample M96 located on eastern basin have two dominant age groups of 113-158 Ma and 400-500 Ma, and the other samples located on southern basin have three prominent age populations at 113-158 Ma, 400-500 Ma and 700-1000 Ma. Samples on different parts of the basin show distinct differences in heavy mineral compositions and they apparently divide into two groups according to the content of rutile (higher or lower than 4%). The spatial variations of zircon-tourmaline-rutile (ZTR) indices are marked by some noticeable increasing trends from basin margins to the inner part of the basin. Compared with the potential source areas, this study clarifies the multiple source characteristics of the Jianghan basin in the composite basin-mountain system. The majority of clastic material was supplied from the north source area through rift-trough sediment-transport pathways, and the eastern, southern and northwestern source areas also contributed detritus to the basin. This clastic material is broadly dispersed in the basin. The early Eocene paleogeography implies that rift architecture and rifting process had an important influence on sediment dispersal. This study shows that integrated zircon U-Pb geochronology and heavy mineral analysis is a useful and powerful method to identify sediment provenance.

  8. Face aftereffects predict individual differences in face recognition ability.

    Science.gov (United States)

    Dennett, Hugh W; McKone, Elinor; Edwards, Mark; Susilo, Tirta

    2012-01-01

    Face aftereffects are widely studied on the assumption that they provide a useful tool for investigating face-space coding of identity. However, a long-standing issue concerns the extent to which face aftereffects originate in face-level processes as opposed to earlier stages of visual processing. For example, some recent studies failed to find atypical face aftereffects in individuals with clinically poor face recognition. We show that in individuals within the normal range of face recognition abilities, there is an association between face memory ability and a figural face aftereffect that is argued to reflect the steepness of broadband-opponent neural response functions in underlying face-space. We further show that this correlation arises from face-level processing, by reporting results of tests of nonface memory and nonface aftereffects. We conclude that face aftereffects can tap high-level face-space, and that face-space coding differs in quality between individuals and contributes to face recognition ability.

  9. Pushing Multiple Convertible Constrains into Frequent Itemsets Mining

    Institute of Scientific and Technical Information of China (English)

    SONG Baoli; QIN Zheng

    2006-01-01

    Constraint pushing techniques have been developed for mining frequent patterns and association rules. However, multiple constraints cannot be handled with existing techniques in frequent pattern mining. In this paper, a new algorithm MCFMC (mining complete set of frequent itemsets with multiple constraints) is introduced. The algorithm takes advantage of the fact that a convertible constraint can be pushed into mining algorithm to reduce mining research spaces. By using a sample database, the algorithm develops techniques which select an optimal method based on a sample database to convert multiple constraints into multiple convertible constraints, disjoined by conjunction and/or, and then partition these constraints into two parts. One part is pushed deep inside the mining process to reduce the research spaces for frequent itemsets, the other part that cannot be pushed in algorithm is used to filter the complete set of frequent itemsets and get the final result. Results from our detailed experiment show the feasibility and effectiveness of the algorithm.

  10. Adjudicating between face-coding models with individual-face fMRI responses.

    Directory of Open Access Journals (Sweden)

    Johan D Carlin

    2017-07-01

    Full Text Available The perceptual representation of individual faces is often explained with reference to a norm-based face space. In such spaces, individuals are encoded as vectors where identity is primarily conveyed by direction and distinctiveness by eccentricity. Here we measured human fMRI responses and psychophysical similarity judgments of individual face exemplars, which were generated as realistic 3D animations using a computer-graphics model. We developed and evaluated multiple neurobiologically plausible computational models, each of which predicts a representational distance matrix and a regional-mean activation profile for 24 face stimuli. In the fusiform face area, a face-space coding model with sigmoidal ramp tuning provided a better account of the data than one based on exemplar tuning. However, an image-processing model with weighted banks of Gabor filters performed similarly. Accounting for the data required the inclusion of a measurement-level population averaging mechanism that approximates how fMRI voxels locally average distinct neuronal tunings. Our study demonstrates the importance of comparing multiple models and of modeling the measurement process in computational neuroimaging.

  11. Human faces are slower than chimpanzee faces.

    Directory of Open Access Journals (Sweden)

    Anne M Burrows

    Full Text Available BACKGROUND: While humans (like other primates communicate with facial expressions, the evolution of speech added a new function to the facial muscles (facial expression muscles. The evolution of speech required the development of a coordinated action between visual (movement of the lips and auditory signals in a rhythmic fashion to produce "visemes" (visual movements of the lips that correspond to specific sounds. Visemes depend upon facial muscles to regulate shape of the lips, which themselves act as speech articulators. This movement necessitates a more controlled, sustained muscle contraction than that produced during spontaneous facial expressions which occur rapidly and last only a short period of time. Recently, it was found that human tongue musculature contains a higher proportion of slow-twitch myosin fibers than in rhesus macaques, which is related to the slower, more controlled movements of the human tongue in the production of speech. Are there similar unique, evolutionary physiologic biases found in human facial musculature related to the evolution of speech? METHODOLOGY/PRINICIPAL FINDINGS: Using myosin immunohistochemistry, we tested the hypothesis that human facial musculature has a higher percentage of slow-twitch myosin fibers relative to chimpanzees (Pan troglodytes and rhesus macaques (Macaca mulatta. We sampled the orbicularis oris and zygomaticus major muscles from three cadavers of each species and compared proportions of fiber-types. Results confirmed our hypothesis: humans had the highest proportion of slow-twitch myosin fibers while chimpanzees had the highest proportion of fast-twitch fibers. CONCLUSIONS/SIGNIFICANCE: These findings demonstrate that the human face is slower than that of rhesus macaques and our closest living relative, the chimpanzee. They also support the assertion that human facial musculature and speech co-evolved. Further, these results suggest a unique set of evolutionary selective pressures on

  12. Unique supply function equilibrium with capacity constraints

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg, Paer [Department of Economics, Uppsala University, P.O. Box 513, SE-751 20 Uppsala (Sweden)

    2008-01-15

    Consider a market where producers submit supply functions to a procurement auction with uncertain demand, e.g. an electricity auction. In the Supply Function Equilibrium (SFE), every firm commits to the supply function that maximises expected profit in the one-shot game given the supply functions of competitors. A basic weakness of the SFE is the presence of multiple equilibria. This paper shows that with (i) symmetric producers, (ii) perfectly inelastic demand, (iii) a price cap, and (iv) capacity constraints that bind with a positive probability, there exists a unique, symmetric SFE. (author)

  13. Seismological Constraints on Geodynamics

    Science.gov (United States)

    Lomnitz, C.

    2004-12-01

    Earth is an open thermodynamic system radiating heat energy into space. A transition from geostatic earth models such as PREM to geodynamical models is needed. We discuss possible thermodynamic constraints on the variables that govern the distribution of forces and flows in the deep Earth. In this paper we assume that the temperature distribution is time-invariant, so that all flows vanish at steady state except for the heat flow Jq per unit area (Kuiken, 1994). Superscript 0 will refer to the steady state while x denotes the excited state of the system. We may write σ 0=(J{q}0ṡX{q}0)/T where Xq is the conjugate force corresponding to Jq, and σ is the rate of entropy production per unit volume. Consider now what happens after the occurrence of an earthquake at time t=0 and location (0,0,0). The earthquake introduces a stress drop Δ P(x,y,z) at all points of the system. Response flows are directed along the gradients toward the epicentral area, and the entropy production will increase with time as (Prigogine, 1947) σ x(t)=σ 0+α {1}/(t+β )+α {2}/(t+β )2+etc A seismological constraint on the parameters may be obtained from Omori's empirical relation N(t)=p/(t+q) where N(t) is the number of aftershocks at time t following the main shock. It may be assumed that p/q\\sim\\alpha_{1}/\\beta times a constant. Another useful constraint is the Mexican-hat geometry of the seismic transient as obtained e.g. from InSAR radar interferometry. For strike-slip events such as Landers the distribution of \\DeltaP is quadrantal, and an oval-shaped seismicity gap develops about the epicenter. A weak outer triggering maxiμm is found at a distance of about 17 fault lengths. Such patterns may be extracted from earthquake catalogs by statistical analysis (Lomnitz, 1996). Finally, the energy of the perturbation must be at least equal to the recovery energy. The total energy expended in an aftershock sequence can be found approximately by integrating the local contribution over

  14. New formulation of Horava-Lifshitz quantum gravity as a master constraint theory

    Energy Technology Data Exchange (ETDEWEB)

    Soo, Chopin, E-mail: cpsoo@mail.ncku.edu.tw [Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan (China); Yang Jinsong, E-mail: Yangksong@gmail.com [Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan (China); Yu, Hoi-Lai, E-mail: hlyu@phys.sinica.edu.tw [Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan (China)

    2011-07-04

    Both projectable and non-projectable versions of Horava-Lifshitz gravity face serious challenges. In the non-projectable version, the constraint algebra is seemingly inconsistent. The projectable version lacks a local Hamiltonian constraint, thus allowing for an extra scalar mode which can be problematic. A new formulation of non-projectable Horava-Lifshitz gravity, naturally realized as a representation of the master constraint algebra studied by loop quantum gravity researchers, is presented. This yields a consistent canonical theory with first class constraints. It captures the essence of Horava-Lifshitz gravity in retaining only spatial diffeomorphisms (instead of full space-time covariance) as the physically relevant non-trivial gauge symmetry; at the same time the local Hamiltonian constraint needed to eliminate the extra mode is equivalently enforced by the master constraint.

  15. Minimal Flavor Constraints for Technicolor

    DEFF Research Database (Denmark)

    Sakuma, Hidenori; Sannino, Francesco

    2010-01-01

    We analyze the constraints on the the vacuum polarization of the standard model gauge bosons from a minimal set of flavor observables valid for a general class of models of dynamical electroweak symmetry breaking. We will show that the constraints have a strong impact on the self-coupling and mas...

  16. Nonholonomic constraints with fractional derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Tarasov, Vasily E [Skobeltsyn Institute of Nuclear Physics, Moscow State University, Moscow 119992 (Russian Federation); Zaslavsky, George M [Courant Institute of Mathematical Sciences, New York University, 251 Mercer St, New York, NY 10012 (United States)

    2006-08-04

    We consider the fractional generalization of nonholonomic constraints defined by equations with fractional derivatives and provide some examples. The corresponding equations of motion are derived using variational principle. We prove that fractional constraints can be used to describe the evolution of dynamical systems in which some coordinates and velocities are related to velocities through a power-law memory function.

  17. An Introduction to 'Creativity Constraints'

    DEFF Research Database (Denmark)

    Onarheim, Balder; Biskjær, Michael Mose

    2013-01-01

    Constraints play a vital role as both restrainers and enablers in innovation processes by governing what the creative agent/s can and cannot do, and what the output can and cannot be. Notions of constraints are common in creativity research, but current contributions are highly dispersed due to n...

  18. Market segmentation using perceived constraints

    Science.gov (United States)

    Jinhee Jun; Gerard Kyle; Andrew Mowen

    2008-01-01

    We examined the practical utility of segmenting potential visitors to Cleveland Metroparks using their constraint profiles. Our analysis identified three segments based on their scores on the dimensions of constraints: Other priorities--visitors who scored the highest on 'other priorities' dimension; Highly Constrained--visitors who scored relatively high on...

  19. On Constraints in Assembly Planning

    Energy Technology Data Exchange (ETDEWEB)

    Calton, T.L.; Jones, R.E.; Wilson, R.H.

    1998-12-17

    Constraints on assembly plans vary depending on product, assembly facility, assembly volume, and many other factors. Assembly costs and other measures to optimize vary just as widely. To be effective, computer-aided assembly planning systems must allow users to express the plan selection criteria that appIy to their products and production environments. We begin this article by surveying the types of user criteria, both constraints and quality measures, that have been accepted by assembly planning systems to date. The survey is organized along several dimensions, including strategic vs. tactical criteria; manufacturing requirements VS. requirements of the automated planning process itself and the information needed to assess compliance with each criterion. The latter strongly influences the efficiency of planning. We then focus on constraints. We describe a framework to support a wide variety of user constraints for intuitive and efficient assembly planning. Our framework expresses all constraints on a sequencing level, specifying orders and conditions on part mating operations in a number of ways. Constraints are implemented as simple procedures that either accept or reject assembly operations proposed by the planner. For efficiency, some constraints are supplemented with special-purpose modifications to the planner's algorithms. Fast replanning enables an interactive plan-view-constrain-replan cycle that aids in constraint discovery and documentation. We describe an implementation of the framework in a computer-aided assembly planning system and experiments applying the system to a number of complex assemblies, including one with 472 parts.

  20. Constraint Programming for Context Comprehension

    DEFF Research Database (Denmark)

    Christiansen, Henning

    2014-01-01

    of knowledge. The language of Constraint Handling Rules, CHR, is suggested for defining constraint solvers that reflect “world knowledge” for the given domain, and driver algorithms may be ex- pressed in Prolog or additional rules of CHR. It is argued that this way of doing context comprehension is an instance...

  1. Robust stability in predictive control with soft constraints

    DEFF Research Database (Denmark)

    Thomsen, Sven Creutz; Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2010-01-01

    In this paper we take advantage of the primary and dual Youla parameterizations for setting up a soft constrained model predictive control (MPC) scheme for which stability is guaranteed in face of norm-bounded uncertainties. Under special conditions guarantees are also given for hard input...... consisting of the primary and dual Youla parameter. This is included in the MPC optimization as a constraint on the induced gain of the optimization variable. We illustrate the method with a numerical simulation example....

  2. Managing retrenchment in French public hospitals: philosophical and regulatory constraints.

    Science.gov (United States)

    Sobczak, P M; Fottler, M D; Chastagner, D

    1988-01-01

    The French hospital system is experiencing economic stresses similar to those experienced by US hospitals. Pressures for cost containment have occurred due to changes in health care funding. The public hospital system is facing unprecedented severe retrenchment. Innovative strategies for managing retrenchment have been restricted by regulatory and philosophical constraints. What is needed is to provide more autonomy for individual hospital managers together with greater accountability for achievement of results.

  3. Level-Set Topology Optimization with Aeroelastic Constraints

    Science.gov (United States)

    Dunning, Peter D.; Stanford, Bret K.; Kim, H. Alicia

    2015-01-01

    Level-set topology optimization is used to design a wing considering skin buckling under static aeroelastic trim loading, as well as dynamic aeroelastic stability (flutter). The level-set function is defined over the entire 3D volume of a transport aircraft wing box. Therefore, the approach is not limited by any predefined structure and can explore novel configurations. The Sequential Linear Programming (SLP) level-set method is used to solve the constrained optimization problems. The proposed method is demonstrated using three problems with mass, linear buckling and flutter objective and/or constraints. A constraint aggregation method is used to handle multiple buckling constraints in the wing skins. A continuous flutter constraint formulation is used to handle difficulties arising from discontinuities in the design space caused by a switching of the critical flutter mode.

  4. Geographic constraints on social network groups.

    Directory of Open Access Journals (Sweden)

    Jukka-Pekka Onnela

    Full Text Available Social groups are fundamental building blocks of human societies. While our social interactions have always been constrained by geography, it has been impossible, due to practical difficulties, to evaluate the nature of this restriction on social group structure. We construct a social network of individuals whose most frequent geographical locations are also known. We also classify the individuals into groups according to a community detection algorithm. We study the variation of geographical span for social groups of varying sizes, and explore the relationship between topological positions and geographic positions of their members. We find that small social groups are geographically very tight, but become much more clumped when the group size exceeds about 30 members. Also, we find no correlation between the topological positions and geographic positions of individuals within network communities. These results suggest that spreading processes face distinct structural and spatial constraints.

  5. Automated Face Recognition System

    Science.gov (United States)

    1992-12-01

    atestfOl.feature-vectjJ -averageljJ); for(j=l; <num-coefsj++) for(i= 5 num-train-faces;i++) sdlQjI -(btrainhil.feaure..vecU1- veagU (btraintil.feature- vecU ... vecU ])* (atest(O1.feature-vecUJ - btrain[iI.feature- vecU ]) + temp; btrain(ii.distance = sqrt ( (double) temp); I**** Store the k-nearest neighbors rank

  6. Auto Industry Faces Change

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A number of indicators show that China's auto industry is facing a new round of large-scale restructuring. When the global auto industry was undergoing reorganization 10 years ago, China's auto industry was in its early stages, acting in a relatively closed market, and thus it missed out on that important event. However, the situation is different today. In the past decade, China's auto industry has grown at a rapid pace. While the world's major transnational companies are

  7. Decoding of faces and face components in face-sensitive human visual cortex

    Directory of Open Access Journals (Sweden)

    David F Nichols

    2010-07-01

    Full Text Available A great challenge to the field of visual neuroscience is to understand how faces are encoded and represented within the human brain. Here we show evidence from functional magnetic resonance imaging (fMRI for spatially distributed processing of the whole face and its components in face-sensitive human visual cortex. We used multi-class linear pattern classifiers constructed with a leave-one-scan-out verification procedure to discriminate brain activation patterns elicited by whole faces, the internal features alone, and the external head outline alone. Furthermore, our results suggest that whole faces are represented disproportionately in the fusiform cortex (FFA whereas the building blocks of faces are represented disproportionately in occipitotemporal cortex (OFA. Faces and face components may therefore be organized with functional clustering within both the FFA and OFA, but with specialization for face components in the OFA and the whole face in the FFA.

  8. Imprinting and flexibility in human face cognition

    Science.gov (United States)

    Marcinkowska, Urszula M.; Terraube, Julien; Kaminski, Gwenaël

    2016-01-01

    Faces are an important cue to multiple physiological and psychological traits. Human preferences for exaggerated sex typicality (masculinity or femininity) in faces depend on multiple factors and show high inter-subject variability. To gain a deeper understanding of the mechanisms underlying facial femininity preferences in men, we tested the interactive effect of family structure (birth order, sibling sex-ratio and number of siblings) and parenthood status on these preferences. Based on a group of 1304 heterosexual men, we have found that preference for feminine faces was not only influenced by sibling age and sex, but also that fatherhood modulated this preference. Men with sisters had a weaker preference for femininity than men with brothers, highlighting a possible effect of a negative imprinting-like mechanism. What is more, fatherhood increased strongly the preference for facial femininity. Finally, for fathers with younger sisters only, the more the age difference increased between them, the more femininity preference increased. Overall our findings bring new insight into how early-acquired experience at the individual level may determine face preference in adulthood, and what is more, how these preferences are flexible and potentially dependent on parenthood status in adult men. PMID:27680495

  9. Face Shape Variation Among Sundanese People from Western Java, Indonesia

    Directory of Open Access Journals (Sweden)

    WOLLY CANDRAMILA

    2015-01-01

    Full Text Available The face is an important visual stimulus in daily life and each face identifies a particular person. The bone structure of the skull along with various soft tissues and coloration influence perception of the face. Facial averageness, and bilateral symmetry are the two most commonly used criterion of facial attractiveness, yet, both may be perceived differently based on hormonal status of the person observed. Facial perceptions may also differ according to cultural norms. In this research, we examined variations in face-shape among Sundanese male and female adults aged 18 to 40. We applied geometric-morphometric methods to analyze the landmark-based morphological variations in the frontal and lateral views of subjects’ faces. We identified five types of female frontal face views and four of male. We also identified five types each of female and male lateral face views. The trichion, gonion and gnathion were three most variable landmarks among the face views in our study, and highly determined the shape of the individuals’ faces. Multiple face type variation may refer to many categories of attractive faces since there is no exactly perfect category in the assessment of facial attractiveness by the viewers. Therefore, we believe that the configuration of facial features cannot constitute the sole visual criterion of facial attractiveness.

  10. Face-space: A unifying concept in face recognition research.

    Science.gov (United States)

    Valentine, Tim; Lewis, Michael B; Hills, Peter J

    2016-10-01

    The concept of a multidimensional psychological space, in which faces can be represented according to their perceived properties, is fundamental to the modern theorist in face processing. Yet the idea was not clearly expressed until 1991. The background that led to the development of face-space is explained, and its continuing influence on theories of face processing is discussed. Research that has explored the properties of the face-space and sought to understand caricature, including facial adaptation paradigms, is reviewed. Face-space as a theoretical framework for understanding the effect of ethnicity and the development of face recognition is evaluated. Finally, two applications of face-space in the forensic setting are discussed. From initially being presented as a model to explain distinctiveness, inversion, and the effect of ethnicity, face-space has become a central pillar in many aspects of face processing. It is currently being developed to help us understand adaptation effects with faces. While being in principle a simple concept, face-space has shaped, and continues to shape, our understanding of face perception.

  11. Evolutionary constraints or opportunities?

    Science.gov (United States)

    Sharov, Alexei A.

    2014-01-01

    Natural selection is traditionally viewed as a leading factor of evolution, whereas variation is assumed to be random and non-directional. Any order in variation is attributed to epigenetic or developmental constraints that can hinder the action of natural selection. In contrast I consider the positive role of epigenetic mechanisms in evolution because they provide organisms with opportunities for rapid adaptive change. Because the term “constraint” has negative connotations, I use the term “regulated variation” to emphasize the adaptive nature of phenotypic variation, which helps populations and species to survive and evolve in changing environments. The capacity to produce regulated variation is a phenotypic property, which is not described in the genome. Instead, the genome acts as a switchboard, where mostly random mutations switch “on” or “off” preexisting functional capacities of organism components. Thus, there are two channels of heredity: informational (genomic) and structure-functional (phenotypic). Functional capacities of organisms most likely emerged in a chain of modifications and combinations of more simple ancestral functions. The role of DNA has been to keep records of these changes (without describing the result) so that they can be reproduced in the following generations. Evolutionary opportunities include adjustments of individual functions, multitasking, connection between various components of an organism, and interaction between organisms. The adaptive nature of regulated variation can be explained by the differential success of lineages in macro-evolution. Lineages with more advantageous patterns of regulated variation are likely to produce more species and secure more resources (i.e., long-term lineage selection). PMID:24769155

  12. Age-dependent face detection and face categorization performance.

    Science.gov (United States)

    Carbon, Claus-Christian; Grüter, Martina; Grüter, Thomas

    2013-01-01

    Empirical studies on the development of face processing skills with age show inconsistent patterns concerning qualitative vs. quantitative changes over time or the age range for peak cognitive performance. In the present study, we tested the proficiency in face detection and face categorization with a large sample of participants (N = 312; age range: 2-88 yrs). As test objects, we used so-called Mooney faces, two-tone (black and white) images of faces lacking critical information of a local, featural and relational nature, reflecting difficult real world face processing conditions. We found that performance in the assessment of gender and age from Mooney faces increases up to about age 15, and decreases from 65 years on. The implications of these findings are discussed in the light of classic and recent findings from face development literature.

  13. CONSTRAINT PROGRAMMING AND UNIVERSITY TIMETABLING

    Directory of Open Access Journals (Sweden)

    G.W. Groves

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The technology of Constraint Programming is rapidly becoming a popular alternative for solving large-scale industry problems. This paper provides an introduction to Constraint Programming and to Constraint Logic Programming (CLP, an enabler of constraint programming. The use of Constraint Logic Programming is demonstrated by describing a system developed for scheduling university timetables. Timetabling problems have a high degree of algorithmic complexity (they are usually NP-Complete, and share features with scheduling problems encountered in industry. The system allows the declaration of both hard requirements, which must always be satisfied, and soft constraints which need not be satisfied, though this would be an advantage.

    AFRIKAANSE OPSOMMING: Hierdie artikel beskryf ’n familie van probleem-oplossingstegnieke bekend as “Constraint Programming”, wat al hoe meer gebruik word om groot-skaalse industriële probleme op te los. Die nut van hierdie tegnieke word gedemonstreer deur die beskrywing van ’n skeduleringsisteem om die roosters vir ’n universiteit te genereer. Roosterskeduleringsprobleme is in praktiese gevalle NP-volledig en deel baie eienskappe met industriële skeduleringsprobleme. Die sisteem wat hier beskryf word maak gebruik van beide harde beperkings (wat altyd bevredig moet word en sagte beperkings (bevrediging hiervan is wel voordelig maar dit is opsioneel.

  14. Multiple Pregnancy

    Science.gov (United States)

    ... Education & Events Advocacy For Patients About ACOG Multiple Pregnancy Home For Patients Search FAQs Multiple Pregnancy Page ... Multiple Pregnancy FAQ188, July 2015 PDF Format Multiple Pregnancy Pregnancy How does multiple pregnancy occur? What are ...

  15. Protocols for Integrity Constraint Checking in Federated Databases

    NARCIS (Netherlands)

    Grefen, Paul; Widom, Jennifer

    1997-01-01

    A federated database is comprised of multiple interconnected database systems that primarily operate independently but cooperate to a certain extent. Global integrity constraints can be very useful in federated databases, but the lack of global queries, global transaction mechanisms, and global conc

  16. A comparative study of face processing using scrambled faces

    OpenAIRE

    Taubert, Jessica; Aagten-Murphy, David; Parr, Lisa A.

    2012-01-01

    It is a widespread assumption that all primate species process faces in the same way because the species are closely related and they engage in similar social interactions. However, this approach ignores potentially interesting and informative differences that may exist between species. This paper describes a comparative study of holistic face processing. Twelve subjects (six chimpanzees Pan troglodytes and six rhesus monkeys Macaca mulatta) were trained to discriminate whole faces (faces wit...

  17. Effective Constraints for Quantum Systems

    CERN Document Server

    Bojowald, Martin; Skirzewski, Aureliano; Tsobanjan, Artur

    2008-01-01

    An effective formalism for quantum constrained systems is presented which allows manageable derivations of solutions and observables, including a treatment of physical reality conditions without requiring full knowledge of the physical inner product. Instead of a state equation from a constraint operator, an infinite system of constraint functions on the quantum phase space of expectation values and moments of states is used. The examples of linear constraints as well as the free non-relativistic particle in parameterized form illustrate how standard problems of constrained systems can be dealt with in this framework.

  18. Face-to-Face Interference in Typical and Atypical Development

    Science.gov (United States)

    Riby, Deborah M.; Doherty-Sneddon, Gwyneth; Whittle, Lisa

    2012-01-01

    Visual communication cues facilitate interpersonal communication. It is important that we look at faces to retrieve and subsequently process such cues. It is also important that we sometimes look away from faces as they increase cognitive load that may interfere with online processing. Indeed, when typically developing individuals hold face gaze…

  19. Interpersonal self-support and attentional disengagement from emotional faces.

    Science.gov (United States)

    Xia, Ling-Xiang; Shi, Xu-Liang; Zhang, Ran-Ran; Hollon, Steven D

    2015-01-08

    Prior studies have shown that interpersonal self-support is related to emotional symptoms. The present study explored the relationship between interpersonal self-support and attentional disengagement from emotional faces. A spatial cueing task was administrated to 21 high and 24 low interpersonal self-support Chinese undergraduate students to assess difficulty in shifting away from emotional faces. The Sidak corrected multiple pairwise tests revealed that the low interpersonal self-support group had greater response latencies on negative faces than neutral faces or positive faces in the invalid cues condition, F(2, 41) = 5.68, p interpersonal self-support group responded more slowly than the high interpersonal self-support group to negative faces, F(1, 42) = 7.63, p interpersonal self-support is related to difficulty disengaging from negative emotional information and suggest that interpersonal self-support may refer to emotional dispositions, especially negative emotional dispositions.

  20. Many Faces of Migrations

    Directory of Open Access Journals (Sweden)

    Milica Antić Gaber

    2013-12-01

    The title “Many faces of migration”, connecting contributions in this special issue, is borrowed from the already mentioned Gallup Institute’s report on global migration (Esipova, 2011. The guiding principle in the selection of the contributions has been their diversity, reflected also in the list of disciplines represented by the authors: sociology, geography, ethnology and cultural anthropology, history, art history, modern Mediterranean studies, gender studies and media studies. Such an approach necessarily leads not only to a diverse, but at least seemingly also incompatib

  1. Faced with a dilemma

    DEFF Research Database (Denmark)

    Christensen, Anne Vinggaard; Christiansen, Anne Hjøllund; Petersson, Birgit

    2013-01-01

    's legal right to choose TOP and considerations about the foetus' right to live were suppressed. Midwives experienced a dilemma when faced with aborted foetuses that looked like newborns and when aborted foetuses showed signs of life after a termination. Furthermore, they were critical of how physicians...... counsel women/couples after prenatal diagnosis. CONCLUSIONS: The midwives' practice in relation to late TOP was characterised by an acknowledgement of the growing ethical status of the foetus and the emotional reactions of the women/couples going through late TOP. Other professions as well as structural...

  2. Multiple sclerosis; Multiple Sklerose

    Energy Technology Data Exchange (ETDEWEB)

    Grunwald, I.Q.; Kuehn, A.L.; Backens, M.; Papanagiotou, P. [Universitaet des Saarlandes, Abteilung fuer Diagnostische und Interventionelle Neuroradiologie, Radiologische Klinik, Homburg/Saar (Germany); Shariat, K. [Universitaet des Saarlandes, Klinik fuer Neurochirurgie, Homburg/Saar (Germany); Kostopoulos, P. [Universitaet des Saarlandes, Klinik fuer Neurologie, Homburg/Saar (Germany)

    2008-06-15

    Multiple sclerosis is the most common chronic inflammatory disease of myelin with interspersed lesions in the white matter of the central nervous system. Magnetic resonance imaging (MRI) plays a key role in the diagnosis and monitoring of white matter diseases. This article focuses on key findings in multiple sclerosis as detected by MRI. (orig.) [German] Die Multiple Sklerose (MS) ist die haeufigste chronisch-entzuendliche Erkrankung des Myelins mit eingesprengten Laesionen im Bereich der weissen Substanz des zentralen Nervensystems. Die Magnetresonanztomographie (MRT) hat bei der Diagnosestellung und Verlaufskontrolle eine Schluesselrolle. Dieser Artikel befasst sich mit Hauptcharakteristika der MR-Bildbebung. (orig.)

  3. Iranian nurses' constraint for research utilization

    Directory of Open Access Journals (Sweden)

    Mehrdad Neda

    2009-09-01

    Full Text Available Abstract Background This paper identifies the views of Iranian clinical nurses regarding the utilization of nursing research in practice. There is a need to understand what restricts Iranian clinical nurses to use research findings. The aim of this study was to identify practicing nurses' view of aspects which they perceived constrain them from research utilization that summarizes and uses research findings to address a nursing practice problem. Methods Data were collected during 6 months by means of face-to face interviews follow by one focus group. Analysis was undertaken using a qualitative content analysis. Results Findings disclosed some key themes perceived by nurses to restrict them to use research findings: level of support require to be research active, to be research minded, the extent of nurses knowledge and skills about research and research utilization, level of educational preparation relating to using research, administration and executive challenges in clinical setting, and theory-practice gap. Conclusion This study identifies constraints that require to be overcome for clinical nurses to actively get involved in research utilization. In this study nurses were generally interested to use research findings. However they felt restricted because of lack of time, lack of peer and manager support and limited knowledge and skills of the research process. This study also confirms that research utilization and the change to research nursing practice are complex issues which require both organizational and educational efforts.

  4. Aquaculture and food crisis: opportunities and constraints.

    Science.gov (United States)

    Liao, I Chiu; Chao, Nai-Hsien

    2009-01-01

    Fish farming, now well known as aquaculture, has been well recognized since the ancient era. The first written document on fish culture was published in China in 475 BC, and the first koi pond was constructed at the Japanese Imperial Palace grounds during 71-130 AD. In recent years, aquaculture has progressively played an important role in the provision of: animal protein and gourmet cuisines, job opportunities, and foreign currency for developing countries. Asian countries produce around 91 percent of the world's total aquaculture production. Among the top ten aquaculture-producing countries, nine are from Asia. The current global population consist of more than 6.5 billion individuals; over one billion of which face hunger problem. In the highly populated Asia-Pacific region with moderately high-productivity, 642 million people are still facing hunger. Being a proficient and potential source of animal protein, aquaculture will play an increasing and important role in solving the world food problem in the future. This paper discusses both the opportunities and constraints in the aquaculture industry, specifically in the Asia-Pacific region, and its possible role in solving the current global food crisis. Strategies including promotion and adoption of traceability and HACCP systems for food safety, and marketing management for aquaculture products are also suggested. It is hoped that traditional administration of aquaculture management for survival, profit, as well as food safety will successfully match sustainability management to meet the urgent global need for food.

  5. Aging changes in the face

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/004004.htm Aging changes in the face To use the sharing ... face with age References Brodie SE, Francis JH. Aging and disorders of the eye. In: Fillit HM, ...

  6. Weighted constraints in generative linguistics.

    Science.gov (United States)

    Pater, Joe

    2009-08-01

    Harmonic Grammar (HG) and Optimality Theory (OT) are closely related formal frameworks for the study of language. In both, the structure of a given language is determined by the relative strengths of a set of constraints. They differ in how these strengths are represented: as numerical weights (HG) or as ranks (OT). Weighted constraints have advantages for the construction of accounts of language learning and other cognitive processes, partly because they allow for the adaptation of connectionist and statistical models. HG has been little studied in generative linguistics, however, largely due to influential claims that weighted constraints make incorrect predictions about the typology of natural languages, predictions that are not shared by the more popular OT. This paper makes the case that HG is in fact a promising framework for typological research, and reviews and extends the existing arguments for weighted over ranked constraints.

  7. Topology Optimization with Stress Constraints

    NARCIS (Netherlands)

    Verbart, A.

    2015-01-01

    This thesis contains contributions to the development of topology optimization techniques capable of handling stress constraints. The research that led to these contributions was motivated by the need for topology optimization techniques more suitable for industrial applications. Currently, topolo

  8. Model-Driven Constraint Programming

    CERN Document Server

    Chenouard, Raphael; Soto, Ricardo; 10.1145/1389449.1389479

    2010-01-01

    Constraint programming can definitely be seen as a model-driven paradigm. The users write programs for modeling problems. These programs are mapped to executable models to calculate the solutions. This paper focuses on efficient model management (definition and transformation). From this point of view, we propose to revisit the design of constraint-programming systems. A model-driven architecture is introduced to map solving-independent constraint models to solving-dependent decision models. Several important questions are examined, such as the need for a visual highlevel modeling language, and the quality of metamodeling techniques to implement the transformations. A main result is the s-COMMA platform that efficiently implements the chain from modeling to solving constraint problems

  9. An Introduction to 'Creativity Constraints'

    DEFF Research Database (Denmark)

    Onarheim, Balder; Biskjaer, Michael Mose

    Constraints play a vital role as both restrainers and enablers in innovation processes by governing what the creative agent/s can and cannot do, and what the output can and cannot be. Notions of constraints are common in creativity research, but current contributions are highly dispersed due...... to no overall conceptual framing or shared terminology. This lack of unity hinders overt opportunities for cross-disciplinary interchange. We argue that an improved understanding of constraints in creativity holds a promising potential for advancements in creativity research across domains and disciplines. Here......, we give an overview of the growing, but incohesive body of research into creativity and constraints, which leads us to introduce ‘creativity constraints’ as a unifying concept to help bridge these disjoint contributions to facilitate cross- disciplinary interchange. Finally, we suggest key topics...

  10. Decentralized systems with design constraints

    CERN Document Server

    Mahmoud, Magdi S

    2014-01-01

    This volume provides a rigorous examination of the analysis, stability and control of large-scale systems, and addresses the difficulties that arise because of dimensionality, information structure constraints, parametric uncertainty and time-delays.

  11. Mathematical Learning Opportunities in Kindergarten through the Use of Digital Tools: Affordances and Constraints

    Directory of Open Access Journals (Sweden)

    Martin Carlsen

    2013-10-01

    Full Text Available This study aims at scrutinising the mathematical learning opportunities of children engaging with digital tools and the emerging affordances and constraints faced in such settings. By adopting a sociocultural perspective on learning and development, the multimodal analysis of the adult–child interaction shows that the children are participants in processes of appropriating the mathematical concepts of sorting and counting. Affordances are taken advantage of by the adults and constraints causing didactical dissonance are overcome and transformed into didactical harmony.

  12. Constraint Programming for Context Comprehension

    DEFF Research Database (Denmark)

    Christiansen, Henning

    2014-01-01

    A close similarity is demonstrated between context comprehension, such as discourse analysis, and constraint programming. The constraint store takes the role of a growing knowledge base learned throughout the discourse, and a suitable con- straint solver does the job of incorporating new pieces o...... of abductive reasoning. The approach fits with possible worlds semantics that allows both standard first-order and non-monotonic semantics....

  13. Formal Verification under Unknown Constraints

    Institute of Scientific and Technical Information of China (English)

    LI Guang-hui; LI Xiao-wei

    2005-01-01

    We present a formal method of verifying designs with unknown constraints (e. g. , black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) formulas. Furthermore, this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

  14. FaceID: A face detection and recognition system

    Energy Technology Data Exchange (ETDEWEB)

    Shah, M.B.; Rao, N.S.V.; Olman, V.; Uberbacher, E.C.; Mann, R.C.

    1996-12-31

    A face detection system that automatically locates faces in gray-level images is described. Also described is a system which matches a given face image with faces in a database. Face detection in an Image is performed by template matching using templates derived from a selected set of normalized faces. Instead of using original gray level images, vertical gradient images were calculated and used to make the system more robust against variations in lighting conditions and skin color. Faces of different sizes are detected by processing the image at several scales. Further, a coarse-to-fine strategy is used to speed up the processing, and a combination of whole face and face component templates are used to ensure low false detection rates. The input to the face recognition system is a normalized vertical gradient image of a face, which is compared against a database using a set of pretrained feedforward neural networks with a winner-take-all fuser. The training is performed by using an adaptation of the backpropagation algorithm. This system has been developed and tested using images from the FERET database and a set of images obtained from Rowley, et al and Sung and Poggio.

  15. A novel thermal face recognition approach using face pattern words

    Science.gov (United States)

    Zheng, Yufeng

    2010-04-01

    A reliable thermal face recognition system can enhance the national security applications such as prevention against terrorism, surveillance, monitoring and tracking, especially at nighttime. The system can be applied at airports, customs or high-alert facilities (e.g., nuclear power plant) for 24 hours a day. In this paper, we propose a novel face recognition approach utilizing thermal (long wave infrared) face images that can automatically identify a subject at both daytime and nighttime. With a properly acquired thermal image (as a query image) in monitoring zone, the following processes will be employed: normalization and denoising, face detection, face alignment, face masking, Gabor wavelet transform, face pattern words (FPWs) creation, face identification by similarity measure (Hamming distance). If eyeglasses are present on a subject's face, an eyeglasses mask will be automatically extracted from the querying face image, and then masked with all comparing FPWs (no more transforms). A high identification rate (97.44% with Top-1 match) has been achieved upon our preliminary face dataset (of 39 subjects) from the proposed approach regardless operating time and glasses-wearing condition.e

  16. Enabling dynamics in face analysis

    NARCIS (Netherlands)

    Dibeklioğlu, H.

    2014-01-01

    Most of the approaches in automatic face analysis rely solely on static appearance. However, temporal analysis of expressions reveals interesting patterns. For a better understanding of the human face, this thesis focuses on temporal changes in the face, and dynamic patterns of expressions. In addit

  17. Forensic Face Recognition: A Survey

    NARCIS (Netherlands)

    Ali, Tauseef; Spreeuwers, Luuk; Veldhuis, Raymond; Quaglia, Adamo; Epifano, Calogera M.

    2012-01-01

    The improvements of automatic face recognition during the last 2 decades have disclosed new applications like border control and camera surveillance. A new application field is forensic face recognition. Traditionally, face recognition by human experts has been used in forensics, but now there is a

  18. Reliability optimization problems with multiple constraints under fuzziness

    Science.gov (United States)

    Gupta, Neha; Haseen, Sanam; Bari, Abdul

    2016-06-01

    In reliability optimization problems diverse situation occurs due to which it is not always possible to get relevant precision in system reliability. The imprecision in data can often be represented by triangular fuzzy numbers. In this manuscript, we have considered different fuzzy environment for reliability optimization problem of redundancy. We formulate a redundancy allocation problem for a hypothetical series-parallel system in which the parameters of the system are fuzzy. Two different cases are then formulated as non-linear programming problem and the fuzzy nature is defuzzified into crisp problems using three different defuzzification methods viz. ranking function, graded mean integration value and α-cut. The result of the methods is compared at the end of the manuscript using a numerical example.

  19. Bilateral hemispheric processing of words and faces: evidence from word impairments in prosopagnosia and face impairments in pure alexia.

    Science.gov (United States)

    Behrmann, Marlene; Plaut, David C

    2014-04-01

    Considerable research has supported the view that faces and words are subserved by independent neural mechanisms located in the ventral visual cortex in opposite hemispheres. On this view, right hemisphere ventral lesions that impair face recognition (prosopagnosia) should leave word recognition unaffected, and left hemisphere ventral lesions that impair word recognition (pure alexia) should leave face recognition unaffected. The current study shows that neither of these predictions was upheld. A series of experiments characterizing speed and accuracy of word and face recognition were conducted in 7 patients (4 pure alexic, 3 prosopagnosic) and matched controls. Prosopagnosic patients revealed mild but reliable word recognition deficits, and pure alexic patients demonstrated mild but reliable face recognition deficits. The apparent comingling of face and word mechanisms is unexpected from a domain-specific perspective, but follows naturally as a consequence of an interactive, learning-based account in which neural processes for both faces and words are the result of an optimization procedure embodying specific computational principles and constraints.

  20. Reentry trajectory optimization for hypersonic vehicle satisfying complex constraints

    Institute of Scientific and Technical Information of China (English)

    Jiang Zhao; Rui Zhou

    2013-01-01

    The reentry trajectory optimization for hypersonic vehicle (HV) is a current problem of great interest. Some complex constraints, such as waypoints for reconnaissance and no-fly zones for threat avoidance, are inevitably involved in a global strike mission. Of the many direct methods, Gauss pseudospectral method (GPM) has been demonstrated as an effective tool to solve the tra-jectory optimization problem with typical constraints. However, a series of difficulties arises for complex constraints, such as the uncertainty of passage time for waypoints and the inaccuracy of approximate trajectory near no-fly zones. The research herein proposes a multi-phase technique based on the GPM to generate an optimal reentry trajectory for HV satisfying waypoint and no-fly zone constraints. Three kinds of specific breaks are introduced to divide the full trajectory into multiple phases. The continuity conditions are presented to ensure a smooth connection between each pair of phases. Numerical examples for reentry trajectory optimization in free-space flight and with complex constraints are used to demonstrate the proposed technique. Simulation results show the feasible application of multi-phase technique in reentry trajectory optimization with way-point and no-fly zone constraints.

  1. The Faces in Infant-Perspective Scenes Change over the First Year of Life.

    Directory of Open Access Journals (Sweden)

    Swapnaa Jayaraman

    Full Text Available Mature face perception has its origins in the face experiences of infants. However, little is known about the basic statistics of faces in early visual environments. We used head cameras to capture and analyze over 72,000 infant-perspective scenes from 22 infants aged 1-11 months as they engaged in daily activities. The frequency of faces in these scenes declined markedly with age: for the youngest infants, faces were present 15 minutes in every waking hour but only 5 minutes for the oldest infants. In general, the available faces were well characterized by three properties: (1 they belonged to relatively few individuals; (2 they were close and visually large; and (3 they presented views showing both eyes. These three properties most strongly characterized the face corpora of our youngest infants and constitute environmental constraints on the early development of the visual system.

  2. Supply Side Constraints on Export Development in Jamaica

    Directory of Open Access Journals (Sweden)

    Marie Freckleton

    2010-11-01

    Full Text Available Este artículo examina los impedimientos por el lado de la oferta que afectan al desarollo de la exportación en Jamaica. El análisis se basa en un examen de exportadores jamaicanos no tradicionales. Los resultados indican que los exportadores jamaicanos hacen frente a impedimientos significativos por el lado de la oferta incluyendo la falta de acceso a capital, insuficiencia de innovaciones, altos costos energéticos y deficiencias infraestructurales. El artículo concluye que en el caso de los países en vías de desarollo afectados por impedimientos por el lado de la oferta se hace necesario tomar medidas que les permitan la ventaja de acceder a los mercados disponibles. En el caso de Jamaica, las medidas requeridas para aliviar los impedimientos por el lado de la oferta incluyen el establecimiento de instituciones financieras de riesgo, el estímulo de la innovación y el desarrollo de la infraestructura. English: This article examines the supply side constraints affecting export development in Jamaica. The analysis is based on a survey of non-traditional exporters. The results of the survey indicates that Jamaican exporters face significant supply side constraints including lack of access to capital, insufficient innovation, high energy costs and infrastructural deficiencies. The article concludes that in the cases of those developing countries facing binding supply side constraints, measures to relax such constraints are necessary to allow them to take full advantage of available market access. In the case of Jamaica, measures required to relax supply side constraints include establishment of venture capital institutions, stimulation of innovation and upgrading of infrastructure.

  3. En-face optical coherence tomography revival

    Science.gov (United States)

    Bradu, Adrian; Kapinchev, Konstantin; Barnes, Frederick; Podoleanu, Adrian Gh.

    2016-03-01

    Quite recently, we introduced a novel Optical Coherence Tomography (OCT) method, termed as Master Slave OCT (MS-OCT), especially to deliver en-face images. MS-OCT operates like a time domain OCT, selecting signal from a selected depth only while scanning the laser beam across the sample. Time domain OCT allows real time production of an en-face image, although relatively slowly. As a major advance, the Master Slave method allows collection of signals from any number of depths, as required by the user. MS-OCT is an OCT method that does not require resampling of data and can be used to deliver en-face images from several depths simultaneously. However, as the MS-OCT method requires important computational resources, the number of multiple depth en-face images produced in real-time is limited. Here, we demonstrate that taking advantage of the parallel processing feature of the MS-OCT technology by harnessing the capabilities of graphics processing units (GPU)s, information from 384 depth positions is acquired in one raster with real time display of 40 en-face OCT images. These exhibit comparable resolution and sensitivity to the images produced using the traditional Fourier domain based method. The GPU facilitates versatile real time selection of parameters, such as the depth positions of the 40 images out of a set of 384 depth locations, as well as their axial resolution. Here, we present in parallel with the 40 en-face OCT images of a human tooth, a confocal microscopy lookalike image, together with two B-scan OCT images along rectangular directions.

  4. Face Processing: Models For Recognition

    Science.gov (United States)

    Turk, Matthew A.; Pentland, Alexander P.

    1990-03-01

    The human ability to process faces is remarkable. We can identify perhaps thousands of faces learned throughout our lifetime and read facial expression to understand such subtle qualities as emotion. These skills are quite robust, despite sometimes large changes in the visual stimulus due to expression, aging, and distractions such as glasses or changes in hairstyle or facial hair. Computers which model and recognize faces will be useful in a variety of applications, including criminal identification, human-computer interface, and animation. We discuss models for representing faces and their applicability to the task of recognition, and present techniques for identifying faces and detecting eye blinks.

  5. Facing the Challenges

    DEFF Research Database (Denmark)

    He, Kai

    2014-01-01

    China's rise signifies a gradual transformation of the international system from unipolarity to a non-unipolar world. ,4s an organization of small and middle powers, ASEAN faces strategic uncertainties brought about by the power transition in the system. Deepening economic interdependence between...... ASEAN and China has amplified the economic cost for the ASEAN states to use traditional military means to deal with China s rise. Applying institutional balancing theory, this paper examines how ASEAN has adopted various institutional instruments, such as the ASEAN Regional Forum (ARF), the East Asia...... Summit (EAS), the Regional Comprehensive Economic Partnership (RCEP), and the ASEAN Community, to constrain and shape China's behaviour in the region in the post-Cold War era. It argues that due to globalization and economic interdependence, the power transition in the 21st century is different from...

  6. Préface

    Directory of Open Access Journals (Sweden)

    Marguerite Mendell

    2008-12-01

    Full Text Available C’est avec grand plaisir que je contribue la préface de ce numéro d’Interventions économiques dédié à la pertinence de la pensée de Karl Polanyi au début du 21ème siècle. Je suis très reconnaissante aux éditeurs, Diane Gabrielle Tremblay, Jean-Marc Fontan et Jean Louis Laville d’avoir pris l’initiative de préparer ce numéro pour le 11ème colloque international de l’Institut Karl Polanyi, qui correspond aussi au 20ème anniversaire de l’Institut, établi à l’Université Concordia en 1988. Interve...

  7. Virtual Professional Learning Communities: Teachers' Perceptions of Virtual Versus Face-to-Face Professional Development

    Science.gov (United States)

    McConnell, Tom J.; Parker, Joyce M.; Eberhardt, Jan; Koehler, Matthew J.; Lundeberg, Mary A.

    2013-06-01

    Research suggests that professional development that engages teachers in instructional inquiry over an extended time through collaborative professional learning communities (PLCs) is effective in improving instruction and student achievement. Still, most professional development is offered as short-duration workshops that are not effective in changing practice. Barriers to the implementation of PLCs include lack of shared meeting time and a shortage of teachers who share the same subject areas or common goals and interests. Convening teachers from multiple districts can alleviate this problem, but teachers are reluctant to travel for meetings due to time and cost restraints. Video-conferencing software offers a solution to these barriers while serving to foster the sense of community needed for PLCs to be effective. The researchers describe the use of Virtual PLCs in which two groups of teachers met monthly for one school year to collaboratively analyze evidence collected as part of their teacher inquiry plans. With help from a facilitator, these groups developed a relationship similar to other groups meeting face-to-face as part of the same professional development program. Analysis of the reflections of teacher-participants and facilitators revealed that teachers prefer face-to-face meetings, but that the virtual and face-to-face meetings provided teachers with similar social interactions in the PLC experience. The findings suggest that teachers perceive videoconferencing as an effective tool for facilitating PLCs when distance and time are practical barriers to face-to-face meetings. Practical considerations for developing and facilitating virtual PLCs are also discussed.

  8. [Comparative studies of face recognition].

    Science.gov (United States)

    Kawai, Nobuyuki

    2012-07-01

    Every human being is proficient in face recognition. However, the reason for and the manner in which humans have attained such an ability remain unknown. These questions can be best answered-through comparative studies of face recognition in non-human animals. Studies in both primates and non-primates show that not only primates, but also non-primates possess the ability to extract information from their conspecifics and from human experimenters. Neural specialization for face recognition is shared with mammals in distant taxa, suggesting that face recognition evolved earlier than the emergence of mammals. A recent study indicated that a social insect, the golden paper wasp, can distinguish their conspecific faces, whereas a closely related species, which has a less complex social lifestyle with just one queen ruling a nest of underlings, did not show strong face recognition for their conspecifics. Social complexity and the need to differentiate between one another likely led humans to evolve their face recognition abilities.

  9. Multisensory constraints on awareness

    Science.gov (United States)

    Deroy, Ophelia; Chen, Yi-Chuan; Spence, Charles

    2014-01-01

    Given that multiple senses are often stimulated at the same time, perceptual awareness is most likely to take place in multisensory situations. However, theories of awareness are based on studies and models established for a single sense (mostly vision). Here, we consider the methodological and theoretical challenges raised by taking a multisensory perspective on perceptual awareness. First, we consider how well tasks designed to study unisensory awareness perform when used in multisensory settings, stressing that studies using binocular rivalry, bistable figure perception, continuous flash suppression, the attentional blink, repetition blindness and backward masking can demonstrate multisensory influences on unisensory awareness, but fall short of tackling multisensory awareness directly. Studies interested in the latter phenomenon rely on a method of subjective contrast and can, at best, delineate conditions under which individuals report experiencing a multisensory object or two unisensory objects. As there is not a perfect match between these conditions and those in which multisensory integration and binding occur, the link between awareness and binding advocated for visual information processing needs to be revised for multisensory cases. These challenges point at the need to question the very idea of multisensory awareness. PMID:24639579

  10. Constraint-based animation: temporal constraints in the Animus systems

    Energy Technology Data Exchange (ETDEWEB)

    Duisberg, R.A.

    1986-01-01

    Algorithm animation has a growing role in computer-aided algorithm design documentation and debugging, since interactive graphics is a richer channel than text for communication. Most animation is currently done laboriously by hand, and it often has the character of canned demonstrations with restricted user interaction. Animus is a system that allows easy construction of an animation with minimal concern for lower-level graphics programming. Constraints are used to describe the appearance and structure of a picture as well as how those pictures evolve in time. The implementation and support of temporal constraints is a substantive extension to previous constraint languages which had only allowed specification of static state. Use of the Animus system is demonstrated in the creation of animations of dynamic mechanical and electrical-circuit simulations, sorting algorithms, problems in operating systems, and geometric curve-drawing algorithms.

  11. Comparing Face Detection and Recognition Techniques

    OpenAIRE

    Korra, Jyothi

    2016-01-01

    This paper implements and compares different techniques for face detection and recognition. One is find where the face is located in the images that is face detection and second is face recognition that is identifying the person. We study three techniques in this paper: Face detection using self organizing map (SOM), Face recognition by projection and nearest neighbor and Face recognition using SVM.

  12. Developmental constraints on behavioural flexibility.

    Science.gov (United States)

    Holekamp, Kay E; Swanson, Eli M; Van Meter, Page E

    2013-05-19

    We suggest that variation in mammalian behavioural flexibility not accounted for by current socioecological models may be explained in part by developmental constraints. From our own work, we provide examples of constraints affecting variation in behavioural flexibility, not only among individuals, but also among species and higher taxonomic units. We first implicate organizational maternal effects of androgens in shaping individual differences in aggressive behaviour emitted by female spotted hyaenas throughout the lifespan. We then compare carnivores and primates with respect to their locomotor and craniofacial adaptations. We inquire whether antagonistic selection pressures on the skull might impose differential functional constraints on evolvability of skulls and brains in these two orders, thus ultimately affecting behavioural flexibility in each group. We suggest that, even when carnivores and primates would theoretically benefit from the same adaptations with respect to behavioural flexibility, carnivores may nevertheless exhibit less behavioural flexibility than primates because of constraints imposed by past adaptations in the morphology of the limbs and skull. Phylogenetic analysis consistent with this idea suggests greater evolutionary lability in relative brain size within families of primates than carnivores. Thus, consideration of developmental constraints may help elucidate variation in mammalian behavioural flexibility.

  13. Elektronická komunikace vs. komunikace face to face

    OpenAIRE

    Pipková, Zuzana

    2009-01-01

    This thesis deals with new forms of communication particularly electronic ones. The main goal is to distinguish electronic communication from face to face communication in a way that differs from traditional media theories. By using examples of the most important medium in electronic communication, Internet, it is shown that nowadays we have such forms of electronic communication that surpass the traditional classification of oral/written communication, immediate/mediate communication, face t...

  14. A host as an ecosystem: Wolbachia coping with environmental constraints.

    Science.gov (United States)

    Sicard, Mathieu; Dittmer, Jessica; Grève, Pierre; Bouchon, Didier; Braquart-Varnier, Christine

    2014-12-01

    The Wolbachia are intracellular endosymbionts widely distributed among invertebrates. These primarily vertically transmitted α-proteobacteria have been intensively studied during the last decades because of their intriguing interactions with hosts, ranging from reproductive manipulations to mutualism. To optimize their vertical transmission from mother to offspring, the Wolbachia have developed fine-tuned strategies. However, the Wolbachia are not restricted to the female gonads and frequently exhibit wide intra-host distributions. This extensive colonization of somatic organs might be necessary for Wolbachia to develop their diverse extended phenotypes. From an endosymbiont's perspective, the within-host environment potentially presents different environmental constraints. Hence, the Wolbachia have to face different intracellular habitats, their host's immune system as well as other microorganisms co-occurring in the same host individual and sometimes even in the same cell. A means for the Wolbachia to protect themselves from these environmental constraints may be to live 'hidden' in vacuoles within host cells. In this review, we summarize the current knowledge regarding the extent of the Wolbachia pandemic and discuss the various environmental constraints these bacteria may have to face within their 'host ecosystem'. Finally, we identify new avenues for future research to better understand the complexity of Wolbachia's interactions with their intracellular environment.

  15. Major Problems Facing Educational Planning in the Next Decade. The Fundamentals of Educational Planning: Lecture-Discussion Series No. 13.

    Science.gov (United States)

    Coombs, Philip H.

    Educational planners will face ten central problems in the next decade. First, there will be a rising demand for education, spurred by continued rapid population growth. Second, educational development will face increasing financial constraints in many countries. Third, educational systems will have to respond to serious shortages of specialized…

  16. [A review of face illusions].

    Science.gov (United States)

    Kitaoka, Akiyoshi

    2012-07-01

    A variety of "face illusions," including the gaze illusion, face inversion effects, geometrical illusions, reversible figures, and other interesting phenomena related to face perception, are reviewed in the present report, with many sample images. The "gaze illusion" or the illusion of eye direction includes the Wollaston illusion, the luminance-induced gaze shift, the Bogart illusion, the eye-shadow-dependent gaze illusion, the Mona Lisa effect, etc. "Face inversion effects" refer to the Thatcher illusion, the fat face-thin illusion, underestimation of the upright face, the nose-shortening illusion of the inverted face, etc. "Geometrical illusions" include the Lee-Freire illusion, Yang's iris illusion, overestimation of the farther eye, the eye-shadow-dependent eye-size illusion, etc. "Reversible figures" contain the whole-part reversible figure, Rubin's vase-face illusion, or hybrid images. "Other interesting phenomena" include the flashed face distortion effect, the presidential illusion, predominance of the mouth or eyebrows over eye expression, the eye direction aftereffect, etc. It is suggested that some of these phenomena are highly specific to face perception.

  17. The effect of familiarity on face adaptation

    OpenAIRE

    Laurence, Sarah

    2013-01-01

    Face adaptation techniques have been used extensively to investigate how faces are processed. It has even been suggested that face adaptation is functional in calibrating the visual system to the diet of faces to which an observer is exposed. Yet most adaptation studies to date have used unfamiliar faces: few have used faces with real world familiarity. Familiar faces have more abstractive representations than unfamiliar faces. The experiments in this thesis therefore examined face adaptation...

  18. Collaborative Representation based Classification for Face Recognition

    CERN Document Server

    Zhang, Lei; Feng, Xiangchu; Ma, Yi; Zhang, David

    2012-01-01

    By coding a query sample as a sparse linear combination of all training samples and then classifying it by evaluating which class leads to the minimal coding residual, sparse representation based classification (SRC) leads to interesting results for robust face recognition. It is widely believed that the l1- norm sparsity constraint on coding coefficients plays a key role in the success of SRC, while its use of all training samples to collaboratively represent the query sample is rather ignored. In this paper we discuss how SRC works, and show that the collaborative representation mechanism used in SRC is much more crucial to its success of face classification. The SRC is a special case of collaborative representation based classification (CRC), which has various instantiations by applying different norms to the coding residual and coding coefficient. More specifically, the l1 or l2 norm characterization of coding residual is related to the robustness of CRC to outlier facial pixels, while the l1 or l2 norm c...

  19. Adaptation improves face trustworthiness discrimination

    Science.gov (United States)

    Keefe, B. D.; Dzhelyova, M.; Perrett, D. I.; Barraclough, N. E.

    2013-01-01

    Adaptation to facial characteristics, such as gender and viewpoint, has been shown to both bias our perception of faces and improve facial discrimination. In this study, we examined whether adapting to two levels of face trustworthiness improved sensitivity around the adapted level. Facial trustworthiness was manipulated by morphing between trustworthy and untrustworthy prototypes, each generated by morphing eight trustworthy and eight untrustworthy faces, respectively. In the first experiment, just-noticeable differences (JNDs) were calculated for an untrustworthy face after participants adapted to an untrustworthy face, a trustworthy face, or did not adapt. In the second experiment, the three conditions were identical, except that JNDs were calculated for a trustworthy face. In the third experiment we examined whether adapting to an untrustworthy male face improved discrimination to an untrustworthy female face. In all experiments, participants completed a two-interval forced-choice (2-IFC) adaptive staircase procedure, in which they judged which face was more untrustworthy. JNDs were derived from a psychometric function fitted to the data. Adaptation improved sensitivity to faces conveying the same level of trustworthiness when compared to no adaptation. When adapting to and discriminating around a different level of face trustworthiness there was no improvement in sensitivity and JNDs were equivalent to those in the no adaptation condition. The improvement in sensitivity was found to occur even when adapting to a face with different gender and identity. These results suggest that adaptation to facial trustworthiness can selectively enhance mechanisms underlying the coding of facial trustworthiness to improve perceptual sensitivity. These findings have implications for the role of our visual experience in the decisions we make about the trustworthiness of other individuals. PMID:23801979

  20. Adaptation improves face trustworthiness discrimination.

    Science.gov (United States)

    Keefe, B D; Dzhelyova, M; Perrett, D I; Barraclough, N E

    2013-01-01

    Adaptation to facial characteristics, such as gender and viewpoint, has been shown to both bias our perception of faces and improve facial discrimination. In this study, we examined whether adapting to two levels of face trustworthiness improved sensitivity around the adapted level. Facial trustworthiness was manipulated by morphing between trustworthy and untrustworthy prototypes, each generated by morphing eight trustworthy and eight untrustworthy faces, respectively. In the first experiment, just-noticeable differences (JNDs) were calculated for an untrustworthy face after participants adapted to an untrustworthy face, a trustworthy face, or did not adapt. In the second experiment, the three conditions were identical, except that JNDs were calculated for a trustworthy face. In the third experiment we examined whether adapting to an untrustworthy male face improved discrimination to an untrustworthy female face. In all experiments, participants completed a two-interval forced-choice (2-IFC) adaptive staircase procedure, in which they judged which face was more untrustworthy. JNDs were derived from a psychometric function fitted to the data. Adaptation improved sensitivity to faces conveying the same level of trustworthiness when compared to no adaptation. When adapting to and discriminating around a different level of face trustworthiness there was no improvement in sensitivity and JNDs were equivalent to those in the no adaptation condition. The improvement in sensitivity was found to occur even when adapting to a face with different gender and identity. These results suggest that adaptation to facial trustworthiness can selectively enhance mechanisms underlying the coding of facial trustworthiness to improve perceptual sensitivity. These findings have implications for the role of our visual experience in the decisions we make about the trustworthiness of other individuals.

  1. Adaptation improves face trustworthiness discrimination

    Directory of Open Access Journals (Sweden)

    Bruce D Keefe

    2013-06-01

    Full Text Available Adaptation to facial characteristics, such as gender and viewpoint, has been shown to both bias our perception of faces and improve facial discrimination. In this study, we examined whether adapting to two levels of face trustworthiness improved sensitivity around the adapted level. Facial trustworthiness was manipulated by morphing between trustworthy and untrustworthy prototypes, each generated by morphing eight trustworthy and eight untrustworthy faces respectively. In the first experiment, just-noticeable differences (JNDs were calculated for an untrustworthy face after participants adapted to an untrustworthy face, a trustworthy face, or did not adapt. In the second experiment, the three conditions were identical, except that JNDs were calculated for a trustworthy face. In the third experiment we examined whether adapting to an untrustworthy male face improved discrimination to an untrustworthy female face. In all experiments, participants completed a two-interval forced-choice adaptive staircase procedure, in which they judged which face was more untrustworthy. JNDs were derived from a psychometric function fitted to the data. Adaptation improved sensitivity to faces conveying the same level of trustworthiness when compared to no adaptation. When adapting to and discriminating around a different level of face trustworthiness there was no improvement in sensitivity and JNDs were equivalent to those in the no adaptation condition. The improvement in sensitivity was found to occur even when adapting to a face with different gender and identity. These results suggest that adaptation to facial trustworthiness can selectively enhance mechanisms underlying the coding of facial trustworthiness to improve perceptual sensitivity. These findings have implications for the role of our visual experience in the decisions we make about the trustworthiness of other individuals.

  2. Face-n-Food: Gender Differences in Tuning to Faces

    Science.gov (United States)

    Pavlova, Marina A.; Scheffler, Klaus; Sokolov, Alexander N.

    2015-01-01

    Faces represent valuable signals for social cognition and non-verbal communication. A wealth of research indicates that women tend to excel in recognition of facial expressions. However, it remains unclear whether females are better tuned to faces. We presented healthy adult females and males with a set of newly created food-plate images resembling faces (slightly bordering on the Giuseppe Arcimboldo style). In a spontaneous recognition task, participants were shown a set of images in a predetermined order from the least to most resembling a face. Females not only more readily recognized the images as a face (they reported resembling a face on images, on which males still did not), but gave on overall more face responses. The findings are discussed in the light of gender differences in deficient face perception. As most neuropsychiatric, neurodevelopmental and psychosomatic disorders characterized by social brain abnormalities are sex specific, the task may serve as a valuable tool for uncovering impairments in visual face processing. PMID:26154177

  3. Comings and Goings: The Multiple Faces of Latin American Diasporas

    Directory of Open Access Journals (Sweden)

    Robert V. Kemper

    2006-04-01

    Full Text Available – Displacements and Diasporas: Asians in the Americas, edited by Wanni W. Anderson and Robert G. Lee. New Brunswick, NJ and London: Rutgers University Press, 2005. – Indigenous Mexican Migrants in the United States, edited by Jonathan Fox and Gaspar Rivera-Salgado. Distributed by Lynn Rienner Publishers for the Center for U.S.-Mexican Studies, UCSD, and the Center for Comparative Immigration Studies, UCSD, 2004. – Diáspora michoacana, edited by Gustavo López Castro. Zamora: El Colegio de Michoacán y el Gobierno del Estado de Michoacán, 2003. – The Japanese in Latin America, by Daniel M. Masterson (with Sayaka FunadaClassen. Urbana and Chicago: University of Illinois Press, 2004. – Jewish Diaspora in Latin America and the Caribbean: Fragments of Memory, edited by Kristin Ruggiero. Brighton, East Sussex: Sussex Academic Press, 2005.

  4. The Multiple Faces of Peer Review in Science Education

    Science.gov (United States)

    Tobin, Kenneth

    2002-04-01

    I use autobiographical narratives to describe and analyse my involvement in peer review activities in science education and to illustrate their historical, social and cultural constitution. I explore ways in which peer review and science education have interrelated in 30-plus years in which I have been a science educator. I employ cultural sociology and activity theory to identify patterns of coherence and coexisting contradictions that create tensions able to catalyse improvements in science education. I argue that early career science educators need a gradual induction into peer review activities, preferably increasing their effectiveness by coparticipating with more experienced colleagues. Also, I critically examine my roles as a peer reviewer, within various contexts that include being an editor of journals and a book series, an examiner of dissertations and an advisor of graduate students, and as a reviewer of applications for tenure and promotion. In so doing I probe power relationships between the reviewer and the reviewed and explore the possibility that peer review is hegemonic. Finally, I present strategies for science educators to reach a collective understanding of how to enact peer review equitably.

  5. Constraint programming and decision making

    CERN Document Server

    Kreinovich, Vladik

    2014-01-01

    In many application areas, it is necessary to make effective decisions under constraints. Several area-specific techniques are known for such decision problems; however, because these techniques are area-specific, it is not easy to apply each technique to other applications areas. Cross-fertilization between different application areas is one of the main objectives of the annual International Workshops on Constraint Programming and Decision Making. Those workshops, held in the US (El Paso, Texas), in Europe (Lyon, France), and in Asia (Novosibirsk, Russia), from 2008 to 2012, have attracted researchers and practitioners from all over the world. This volume presents extended versions of selected papers from those workshops. These papers deal with all stages of decision making under constraints: (1) formulating the problem of multi-criteria decision making in precise terms, (2) determining when the corresponding decision problem is algorithmically solvable; (3) finding the corresponding algorithms, and making...

  6. Learning to Discriminate Face Views

    Directory of Open Access Journals (Sweden)

    Fang Fang

    2011-05-01

    Full Text Available Although visual feature leaning has been well studied, we still know little about the mechanisms of perceptual learning of complex object. Here, human perceptual learning in discrimination of in-depth orientation of face view was studied using psychophysics, EEG and fMRI. We trained subjects to discriminate face orientations around a face view (i.e. 30° over eight daily sessions, which resulted in a significant improvement in sensitivity to the face view orientation. This improved sensitivity was highly specific to the trained orientation and persisted up to six months. Different from perceptual learning of simple visual features, this orientation-specific learning effect could completely transfer across changes in face size, visual field and face identity. A complete transfer also occurred between two partial face images that were mutually exclusive but constituted a complete face. However, the transfer of the learning effect between upright and inverted faces and between a face and a paperclip object was very weak. Before and after training, we measured EEG and fMRI BOLD signals responding to both the trained and the untrained face views. Analyses of ERPs and induced gamma activity showed that face view discrimination training led to a larger reduction of N170 latency at the left occipital-temporal area and a concurrent larger decrease of induced gamma activity at the left frontal area with the trained face view, compared with the untrained ones. BOLD signal amplitude and MVPA analyses showed that, in face-selective cortical areas, training did not lead to a significant amplitude change, but induced a more reliable spatial pattern of neural activity in the left FFA. These results suggest that the visual system had learned how to compute face orientation from face configural information more accurately and that a large amount of plastic changes took place at a level of higher visual processing where size-, location-, and identity

  7. Facing the Crises

    Directory of Open Access Journals (Sweden)

    Moira Baker

    2014-12-01

    Full Text Available Timely, provocative, and theoretically sophisticated, the essays comprising In the Face of Crises: Anglophone Literature in the Postmodern World situate their work amid several critical global concerns: the devastation wreaked by global capitalism following the worldwide financial crash, the financial sector’s totalizing grip upon the world economy, the challenge to traditional definitions of “human nature” and identity posed by technologies of the body and of warfare, the quest of indigenous communities for healing from the continuing traumatic effects of colonization, and the increasing corporatization of the academy as an apparatus of the neo-liberal state – to specify only a few. Edited by Professors Ljubica Matek and Jasna Poljak Rehlicki, these essays deploy a broad range of contemporary theories, representing recent developments in cultural studies, the new economic criticism, postcolonial film studies, feminism and gender studies, and the new historicism. The eleven essays selected by Matek and Rehlicki offer convincing support for their claim that humanistic research delving into Anglophone literature, far from being a “non-profitable” pursuit in an increasingly technologized society, affords clarifying insights into contemporary “economic, cultural, and social processes in the globalizing and globalized culture of the West” (ix.

  8. Face au risque

    CERN Document Server

    Grosse, Christian; November, Valérie

    2007-01-01

    Ce volume collectif sur le risque inaugure la collection L'ÉQUINOXE. Ancré dans l'histoire pour mesurer les continuités et les ruptures, il illustre la manière dont les sciences humaines évaluent et mesurent les enjeux collectifs du risque sur les plans politiques, scientifiques, énergétiques, juridiques et éthiques. Puisse-t-il nourrir la réflexion sur la culture et la prévention du risque. Ses formes épidémiques, écologiques, sociales, terroristes et militaires nourrissent les peurs actuelles, structurent les projets sécuritaires et constituent - sans doute - les défis majeurs à notre modernité. Dans la foulée de la richesse scientifique d'Equinoxe, L'ÉQUINOXE hérite de son esprit en prenant à son tour le pari de contribuer - non sans risque - à enrichir en Suisse romande et ailleurs le champ éditorial des sciences humaines dont notre société a besoin pour forger ses repères. Après Face au risque suivra cet automne Du sens des Lumières. (MICHEL PORRET Professeur Ordinaire à la F...

  9. Multi-feature fusion for thermal face recognition

    Science.gov (United States)

    Bi, Yin; Lv, Mingsong; Wei, Yangjie; Guan, Nan; Yi, Wang

    2016-07-01

    Human face recognition has been researched for the last three decades. Face recognition with thermal images now attracts significant attention since they can be used in low/none illuminated environment. However, thermal face recognition performance is still insufficient for practical applications. One main reason is that most existing work leverage only single feature to characterize a face in a thermal image. To solve the problem, we propose multi-feature fusion, a technique that combines multiple features in thermal face characterization and recognition. In this work, we designed a systematical way to combine four features, including Local binary pattern, Gabor jet descriptor, Weber local descriptor and Down-sampling feature. Experimental results show that our approach outperforms methods that leverage only a single feature and is robust to noise, occlusion, expression, low resolution and different l1 -minimization methods.

  10. Procedural design of exterior lighting for buildings with complex constraints

    KAUST Repository

    Schwarz, Michael

    2014-09-23

    We present a system for the lighting design of procedurally modeled buildings. The design is procedurally specified as part of the ordinary modeling workflow by defining goals for the illumination that should be attained and locations where luminaires may be installed to realize these goals. Additionally, constraints can be modeled that make the arrangement of the installed luminaires respect certain aesthetic and structural considerations. From this specification, the system automatically generates a lighting solution for any concrete model instance. The underlying, intricate joint optimization and constraint satisfaction problem is approached with a stochastic scheme that operates directly in the complex subspace where all constraints are observed. To navigate this subspace efficaciously, the actual lighting situation is taken into account. We demonstrate our system on multiple examples spanning a variety of architectural structures and lighting designs. Copyright held by the Owner/Author.

  11. Face adaptation improves gender discrimination.

    Science.gov (United States)

    Yang, Hua; Shen, Jianhong; Chen, Juan; Fang, Fang

    2011-01-01

    Adaptation to a visual pattern can alter the sensitivities of neuronal populations encoding the pattern. However, the functional roles of adaptation, especially in high-level vision, are still equivocal. In the present study, we performed three experiments to investigate if face gender adaptation could affect gender discrimination. Experiments 1 and 2 revealed that adapting to a male/female face could selectively enhance discrimination for male/female faces. Experiment 3 showed that the discrimination enhancement induced by face adaptation could transfer across a substantial change in three-dimensional face viewpoint. These results provide further evidence suggesting that, similar to low-level vision, adaptation in high-level vision could calibrate the visual system to current inputs of complex shapes (i.e. face) and improve discrimination at the adapted characteristic.

  12. Holistic face training enhances face processing in developmental prosopagnosia.

    Science.gov (United States)

    DeGutis, Joseph; Cohan, Sarah; Nakayama, Ken

    2014-06-01

    Prosopagnosia has largely been regarded as an untreatable disorder. However, recent case studies using cognitive training have shown that it is possible to enhance face recognition abilities in individuals with developmental prosopagnosia. Our goal was to determine if this approach could be effective in a larger population of developmental prosopagnosics. We trained 24 developmental prosopagnosics using a 3-week online face-training program targeting holistic face processing. Twelve subjects with developmental prosopagnosia were assessed before and after training, and the other 12 were assessed before and after a waiting period, they then performed the training, and were then assessed again. The assessments included measures of front-view face discrimination, face discrimination with view-point changes, measures of holistic face processing, and a 5-day diary to quantify potential real-world improvements. Compared with the waiting period, developmental prosopagnosics showed moderate but significant overall training-related improvements on measures of front-view face discrimination. Those who reached the more difficult levels of training ('better' trainees) showed the strongest improvements in front-view face discrimination and showed significantly increased holistic face processing to the point of being similar to that of unimpaired control subjects. Despite challenges in characterizing developmental prosopagnosics' everyday face recognition and potential biases in self-report, results also showed modest but consistent self-reported diary improvements. In summary, we demonstrate that by using cognitive training that targets holistic processing, it is possible to enhance face perception across a group of developmental prosopagnosics and further suggest that those who improved the most on the training task received the greatest benefits.

  13. Multi—pose Color Face Recognition in a Complex Background

    Institute of Scientific and Technical Information of China (English)

    ZHUChangren; WANGRunsheng

    2003-01-01

    Face recognition has wider application fields. In recurrent references, most of the algorithms that deal with the face recognition in the static images are with simple background, and only used for ID picture recogni-tion. It is necessary to study the whole process of multi-pose face recognition in a clutter background. In this pa-per an automatic multi-pose face recognition system with multi-feature is proposed. It consists of several steps: face detection, detection and location of the face organs, feature extraction for recognition, recognition decision. In face de-tection the combination of skin-color and multi-verification which consists of the analysis of the shape, local organ fea-tures and head model is applied to improve the perfor-mance. In detection and location of the face organ feature points, with the analysis of multiple features and their pro-jections, the combination of an iterative search with a con-fidence function and template matching at the candidate points is adopted to improve the performance of accuracy and speed. In feature extraction for recognition, geome-try normalization based on three-point afflne transform is adopted to conserve the information to a maximum con-tent before the feature extraction of principal component analysis (PCA). In recognition decision, a hierarchical face model with the division of the face poses is introduced to reduce its retrieval space and thus to cut its time consump-tion. In addition, a fusion decision is applied to improve the face recognition performance. Also, pose recognition result can be got simultaneously. The new approach is ap-plied to 420 color images which consist of multi-pose faces with two visible eyes in a complex background, and the results are satisfactory.

  14. Miliary Osteoma Cutis of the Face: A Case

    Directory of Open Access Journals (Sweden)

    Selma Emre

    2014-03-01

    Full Text Available Osteoma cutis (cutaneous ossification (OC is a rare disorder with true bone formation within the skin. Multiple miliary osteoma cutis of the face (MMOCF is a cause of acquired OC, is characterized by multiple, small, and primary osteomas in the skin tissue of the face and is a benign extraskeletal and rare bone formation. To date, 52 cases with MMOCF have been reported in the literature. Herein, we report a 56-year-old female patient presented with multiple small, firm, skin-colored papules on the forehead and face lasting for 4 years. She had no history of preexisting acne or any local inflammatory disease at the lesional sites. The skin biopsy revealed osteoid formation with central degeneration and calcification in the dermis. Depending on these clinical and histopathological findings, the patient was diagnosed as MMOCF.

  15. [Neural basis of self-face recognition: social aspects].

    Science.gov (United States)

    Sugiura, Motoaki

    2012-07-01

    Considering the importance of the face in social survival and evidence from evolutionary psychology of visual self-recognition, it is reasonable that we expect neural mechanisms for higher social-cognitive processes to underlie self-face recognition. A decade of neuroimaging studies so far has, however, not provided an encouraging finding in this respect. Self-face specific activation has typically been reported in the areas for sensory-motor integration in the right lateral cortices. This observation appears to reflect the physical nature of the self-face which representation is developed via the detection of contingency between one's own action and sensory feedback. We have recently revealed that the medial prefrontal cortex, implicated in socially nuanced self-referential process, is activated during self-face recognition under a rich social context where multiple other faces are available for reference. The posterior cingulate cortex has also exhibited this activation modulation, and in the separate experiment showed a response to attractively manipulated self-face suggesting its relevance to positive self-value. Furthermore, the regions in the right lateral cortices typically showing self-face-specific activation have responded also to the face of one's close friend under the rich social context. This observation is potentially explained by the fact that the contingency detection for physical self-recognition also plays a role in physical social interaction, which characterizes the representation of personally familiar people. These findings demonstrate that neuroscientific exploration reveals multiple facets of the relationship between self-face recognition and social-cognitive process, and that technically the manipulation of social context is key to its success.

  16. Holistic processing predicts face recognition.

    Science.gov (United States)

    Richler, Jennifer J; Cheung, Olivia S; Gauthier, Isabel

    2011-04-01

    The concept of holistic processing is a cornerstone of face-recognition research. In the study reported here, we demonstrated that holistic processing predicts face-recognition abilities on the Cambridge Face Memory Test and on a perceptual face-identification task. Our findings validate a large body of work that relies on the assumption that holistic processing is related to face recognition. These findings also reconcile the study of face recognition with the perceptual-expertise work it inspired; such work links holistic processing of objects with people's ability to individuate them. Our results differ from those of a recent study showing no link between holistic processing and face recognition. This discrepancy can be attributed to the use in prior research of a popular but flawed measure of holistic processing. Our findings salvage the central role of holistic processing in face recognition and cast doubt on a subset of the face-perception literature that relies on a problematic measure of holistic processing.

  17. Winning Faces Vary By Ideology

    DEFF Research Database (Denmark)

    Laustsen, Lasse; Petersen, Michael Bang

    2016-01-01

    for others. Utilizing research on ideological stereotypes and the determinants of facial preferences, we focus on the relationship between the facial dominance of the source and the ideology of the receiver. Across five studies, we demonstrate that a dominant face is a winning face when the audience...... is conservative but backfires and decreases success when the audience is liberal. On the other hand, a non-dominant face constitutes a winning face among liberal audiences but backfires among conservatives. These effects seemingly stem from deep-seated psychological responses and shape both the election...

  18. Study of Face Recognition Techniques

    Directory of Open Access Journals (Sweden)

    Sangeeta Kaushik

    2014-12-01

    Full Text Available A study of both face recognition and detection techniques is carried out using the algorithms like Principal Component Analysis (PCA, Kernel Principal Component Analysis (KPCA, Linear Discriminant Analysis (LDA and Line Edge Map (LEM. These algorithms show different rates of accuracy under different conditions. The automatic recognition of human faces presents a challenge to the pattern recognition community. Typically, human faces are different in shapes with minor similarity from person to person. Furthermore, lighting condition changes, facial expressions and pose variations further complicate the face recognition task as one of the difficult problems in pattern analysis.

  19. Teaching On-Line versus Face-to-Face.

    Science.gov (United States)

    Smith, Glenn Gordon; Ferguson, David; Caris, Mieke

    2002-01-01

    Investigates and describes the current instructor experience of teaching college courses over the Web versus in face-to-face formats in terms of teaching strategies, social issues, and media effects. Discusses communication styles, relationship between students and instructors, instructor workload, and discussion patterns, and proposes a model…

  20. Effects of aging on face identification and holistic face processing.

    Science.gov (United States)

    Konar, Yaroslav; Bennett, Patrick J; Sekuler, Allison B

    2013-08-09

    Several studies have shown that face identification accuracy is lower in older than younger adults. This effect of aging might be due to age differences in holistic processing, which is thought to be an important component of human face processing. Currently, however, there is conflicting evidence as to whether holistic face processing is impaired in older adults. The current study therefore re-examined this issue by measuring response accuracy in a 1-of-4 face identification task and the composite face effect (CFE), a common index of holistic processing, in older adults. Consistent with previous reports, we found that face identification accuracy was lower in older adults than in younger adults tested in the same task. We also found a significant CFE in older adults that was similar in magnitude to the CFE measured in younger subjects with the same task. Finally, we found that there was a significant positive correlation between the CFE and face identification accuracy. This last result differs from the results obtained in a previous study that used the same tasks and which found no evidence of an association between the CFE and face identification accuracy in younger adults. Furthermore, the age difference was found with subtraction-, regression-, and ratio-based estimates of the CFE. The current findings are consistent with previous claims that older adults rely more heavily on holistic processing to identify objects in conditions of limited processing resources.

  1. Registration of 3D Face Scans with Average Face Models

    NARCIS (Netherlands)

    Salah, A.A.; Alyuz, N.; Akarun, L.

    2008-01-01

    The accuracy of a 3D face recognition system depends on a correct registration that aligns the facial surfaces and makes a comparison possible. The best results obtained so far use a costly one-to-all registration approach, which requires the registration of each facial surface to all faces in the g

  2. Addressee Identification In Face-to-Face Meetings

    NARCIS (Netherlands)

    Jovanovic, N.; op den Akker, Hendrikus J.A.; Nijholt, Antinus; McCarthy, D.; Wintner, S.

    We present results on addressee identification in four-participants face-to-face meetings using Bayesian Network and Naive Bayes classifiers. First, we investigate how well the addressee of a dialogue act can be predicted based on gaze, utterance and conversational context features. Then, we explore

  3. Cyber- and Face-to-Face Bullying: Who Crosses Over?

    Science.gov (United States)

    Shin, Hwayeon Helene; Braithwaite, Valerie; Ahmed, Eliza

    2016-01-01

    A total of 3956 children aged 12-13 years who completed the Longitudinal Study of Australian Children (LSAC Wave 5) were studied about their experiences of traditional face-to-face bullying and cyberbullying in the last month. In terms of prevalence, sixty percent of the sample had been involved in traditional bullying as the victim and/or the…

  4. Finding Hope in the Face-to-Face.

    Science.gov (United States)

    Edgoose, Jennifer Y C; Edgoose, Julian M

    2017-05-01

    What does it mean to look into the face of a patient who looks back? Face-to-face encounters are at the heart of the patient-clinician relationship but their singular significance is often lost amid the demands of today's high-tech, metric-driven health care systems. Using the framework provided by the philosopher and Holocaust survivor Emmanuel Levinas, the authors explore the unique responsibility and potential for hope found only in face-to-face encounters. Revisiting this most fundamental attribute of medicine is likely our greatest chance to reclaim who we are as clinicians and why we do what we do. © 2017 Annals of Family Medicine, Inc.

  5. Constraints on axion inflation from the weak gravity conjecture

    Energy Technology Data Exchange (ETDEWEB)

    Rudelius, Tom [Jefferson Physical Laboratory, Harvard University,Cambridge, MA 02138 (United States)

    2015-09-08

    We derive constraints facing models of axion inflation based on decay constant alignment from a string-theoretic and quantum gravitational perspective. In particular, we investigate the prospects for alignment and ‘anti-alignment’ of C{sub 4} axion decay constants in type IIB string theory, deriving a strict no-go result in the latter case. We discuss the relationship of axion decay constants to the weak gravity conjecture and demonstrate agreement between our string-theoretic constraints and those coming from the ‘generalized’ weak gravity conjecture. Finally, we consider a particular model of decay constant alignment in which the potential of C{sub 4} axions in type IIB compactifications on a Calabi-Yau three-fold is dominated by contributions from D7-branes, pointing out that this model evades some of the challenges derived earlier in our paper but is highly constrained by other geometric considerations.

  6. Constraints on the development of biotechnology in Zambia.

    Science.gov (United States)

    Lewanika, M M; Mulenga, K D

    1996-09-01

    Biotechnology can play an essential role in fostering the economic and social development of developing countries like Zambia. However, due to a number of constraints, Zambia is not in a position to exploit the emerging opportunities from biotechnology. Prominent among these constraints are the lack of a biotechnology policy, an insufficient number of trained personnel, a poor science and technology base and very little basic research in universities and research institutions. The challenge Zambia must overcome is to establish a capacity and capability to innovate its own biotechnology as well as to adapt biotechnologies developed elsewhere to the Zambian conditions and environment. Despite all the hurdles and setbacks Zambia will face as she endeavours to enter the world of biotechnology, Zambia cannot afford to be a mere spectator as the rest of the world invests and benefits from the promise of biotechnology.

  7. Thinking aloud in the presence of interruptions and time constraints

    DEFF Research Database (Denmark)

    Hertzum, Morten; Holmegaard, Kristin Due

    2013-01-01

    Thinking aloud is widely used for usability evaluation and its reactivity is therefore important to the quality of evaluation results. This study investigates whether thinking aloud (i.e., verbalization at levels 1 and 2) affects the behaviour of users who perform tasks that involve interruptions...... and time constraints, two frequent elements of real-world activities. We find that the presence of auditory, visual, audiovisual, or no interruptions interacts with thinking aloud for task solution rate, task completion time, and participants’ fixation rate. Thinking-aloud participants also spend longer...... responding to interruptions than control participants. Conversely, the absence or presence of time constraints does not interact with thinking aloud, suggesting that time pressure is less likely to make thinking aloud reactive than previously assumed. Our results inform practitioners faced with the decision...

  8. Resource constraints and strategic change in a public hospital system.

    Science.gov (United States)

    Champagne, F; Langley, A; Denis, J L; Contandriopoulos, A P; Cazale, L; Rivard, M

    1997-08-01

    It has been suggested that strategic management in public services tends to be oriented towards preserving and perpetuating current patterns of service provision, rather than changing priorities. However, faced with severe resource constraints combined with growing demand and rapidly developing technology, public hospitals in Canada have come under increasing pressure. Based on an empirical study of strategic management and change in 32 Montreal hospitals, this paper examines the relationship between financial adversity and the extent and nature of strategic change in these organizations. Strategic change indicators considered in the study include overall product mix, product diversity, product complexity, market demographics, efficiency, and revenue diversification. Results suggest that resource constraints have indeed stimulated changes within these organizations. In particular, hospitals suffering more severe financial difficulties have reduced their size and focused on a narrower range of services. Moreover, there is evidence that greater complementarity has been achieved among the entire sample of hospitals.

  9. Facing the Audience

    DEFF Research Database (Denmark)

    Frølunde, Lisbeth

    2013-01-01

    and audience. Dialogic theory is applied toward an exploration of how humans make meaning (semiosis) on the basis of previous experience or knowledge. Three main Bakhtinian concepts are discussed in an attempt to gain understand theoretical understanding of the hybrid animated film: heteroglossia (multiple......This chapter explores machinima as a "hybrid animated film" or "hybrid text", with focus on the combination of machinima animation and live-action imagery. Machinima is used as an example of how "novel" or new forms of text evolve. The meaning-making processes of machinima filmmakers and audiences...... linguistic and cultural evolutions, and may even propel them. This essay concerns the dialogic theories on language and culture inspired by the Russian literary philosopher M. M. Bakhtin (1895-1975) applied to understanding machinima (realtime animation), which is seen as an example of “hybrid animated film...

  10. 人脸识别考勤系统联合信息平台提高首台手术准时率%Application of face recognition based time attendance system combined with multiple communication systems to operating room to boost punctual start of the first surgery of the day

    Institute of Scientific and Technical Information of China (English)

    罗忠梅; 曹阳慧; 张相云; 周淑云; 雷菊红

    2012-01-01

    目的 探讨人脸识别考勤系统联合信息系统提高首台手术准时率的效果.方法 选择2012年1~4月首台手术的1 790例作为观察组,采取人脸识别考勤系统联合手术麻醉信息系统、短信提醒系统、手术信息显示系统多部门协作进行管理.选择2011年1~4月首台手术1 548例作为对照组,采取巡回护士电话催促手术医生到位、护士长登记上报的方式管理.结果 观察组首台手术准时率较对照组显著上升,因手术医生迟到造成首台手术未准时开台率显著下降(均P<0.01).结论 加强首台手术准时开始工作的管理非常必要,人脸识别考勤系统及各信息平台优势明显,提高了首台手术的准时率.%Objective To explore whether the application of face recognition based time attendance system combined with multiple communication systems improve punctual start of the first surgery of the day. Methods A total of 1790 cases receiving their surgery as the first one of the day from January to April of 2012 were assigned into an observation group, for which a face recognition based time attendance system combined with surgical anesthesia system, text messaging system, operation information display system were applied and multi-sector collaboration was achieved. Totally , 1548 cases as counterparts from January to April in 2011 were taken as the control group, for which, circulating nurses made phone calls to push surgeons to be on time for the first surgery. For surgeons who failed to arrive on time, the head nurses wrote down their names and frequency of delays and reported to supervising departments. Results The rate of on-time start of the first operation in the observation group was significantly higher than that in the control group, rate of delayed start of the first surgery due to surgeons being late dropped significantly (P<0. 01 for both). Conclusion It is very necessary to reinforce on-time start of the first operation of the day

  11. Excitability constraints on voltage-gated sodium channels.

    Directory of Open Access Journals (Sweden)

    Elaine Angelino

    2007-09-01

    Full Text Available We study how functional constraints bound and shape evolution through an analysis of mammalian voltage-gated sodium channels. The primary function of sodium channels is to allow the propagation of action potentials. Since Hodgkin and Huxley, mathematical models have suggested that sodium channel properties need to be tightly constrained for an action potential to propagate. There are nine mammalian genes encoding voltage-gated sodium channels, many of which are more than approximately 90% identical by sequence. This sequence similarity presumably corresponds to similarity of function, consistent with the idea that these properties must be tightly constrained. However, the multiplicity of genes encoding sodium channels raises the question: why are there so many? We demonstrate that the simplest theoretical constraints bounding sodium channel diversity--the requirements of membrane excitability and the uniqueness of the resting potential--act directly on constraining sodium channel properties. We compare the predicted constraints with functional data on mammalian sodium channel properties collected from the literature, including 172 different sets of measurements from 40 publications, wild-type and mutant, under a variety of conditions. The data from all channel types, including mutants, obeys the excitability constraint; on the other hand, channels expressed in muscle tend to obey the constraint of a unique resting potential, while channels expressed in neuronal tissue do not. The excitability properties alone distinguish the nine sodium channels into four different groups that are consistent with phylogenetic analysis. Our calculations suggest interpretations for the functional differences between these groups.

  12. Intertemporal consumption and credit constraints

    DEFF Research Database (Denmark)

    Leth-Petersen, Søren

    2010-01-01

    There is continuing controversy over the importance of credit constraints. This paper investigates whether total household expenditure and debt is affected by an exogenous increase in access to credit provided by a credit market reform that enabled Danish house owners to use housing equity as col...

  13. Perceptual Constraints in Phonotactic Learning

    Science.gov (United States)

    Endress, Ansgar D.; Mehler, Jacques

    2010-01-01

    Structural regularities in language have often been attributed to symbolic or statistical general purpose computations, whereas perceptual factors influencing such generalizations have received less interest. Here, we use phonotactic-like constraints as a case study to ask whether the structural properties of specific perceptual and memory…

  14. Sterile neutrino constraints from cosmology

    DEFF Research Database (Denmark)

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G.

    2012-01-01

    The presence of light particles beyond the standard model's three neutrino species can profoundly impact the physics of decoupling and primordial nucleosynthesis. I review the observational signatures of extra light species, present constraints from recent data, and discuss the implications...... of possible sterile neutrinos with O(eV)-masses for cosmology....

  15. Sterile neutrino constraints from cosmology

    DEFF Research Database (Denmark)

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G.;

    2012-01-01

    The presence of light particles beyond the standard model's three neutrino species can profoundly impact the physics of decoupling and primordial nucleosynthesis. I review the observational signatures of extra light species, present constraints from recent data, and discuss the implications of po...

  16. Constraint-based facial animation

    NARCIS (Netherlands)

    Z.M. Ruttkay

    1999-01-01

    textabstractConstraints have been traditionally used for computer animation applications to define side conditions for generating synthesized motion according to a standard, usually physically realistic, set of motion equations. The case of facial animation is very different, as no set of motion equ

  17. Constraint-induced movement therapy

    DEFF Research Database (Denmark)

    Castellini, Greta; Gianola, Silvia; Banzi, Rita;

    2014-01-01

    on randomized controlled trials (RCTs) included in a Cochrane systematic review on the effectiveness of constraint-induced movement therapy (CIMT) for stroke patients. METHODS: We extracted data on the functional independence measure (FIM) and the action research arm test (ARAT) from RCTs that compared CIMT...

  18. Constraint Programming versus Mathematical Programming

    DEFF Research Database (Denmark)

    Hansen, Jesper

    2003-01-01

    Constraint Logic Programming (CLP) is a relatively new technique from the 80's with origins in Computer Science and Artificial Intelligence. Lately, much research have been focused on ways of using CLP within the paradigm of Operations Research (OR) and vice versa. The purpose of this paper...

  19. Observational constraints on cluster evolution

    NARCIS (Netherlands)

    Larsen, S.S.|info:eu-repo/dai/nl/304833347

    2008-01-01

    Current observational constraints on the dynamical evolution of star clusters are reviewed. Theory and observations now agree nicely on the mass dependency and time scales for disruption of young star clusters in galactic disks, but many problems still await resolution. The origin of the mass

  20. Constraint-based facial animation

    NARCIS (Netherlands)

    Z.M. Ruttkay

    1999-01-01

    textabstractConstraints have been traditionally used for computer animation applications to define side conditions for generating synthesized motion according to a standard, usually physically realistic, set of motion equations. The case of facial animation is very different, as no set of motion

  1. The Use of Neural Networks in Real-time Face Detection

    Directory of Open Access Journals (Sweden)

    Kevin Curran

    2005-01-01

    Full Text Available As continual research is being conducted in the area of computer vision, one of the most practical applications under vigorous development is in the construction of a robust real-time face detection system. Successfully constructing a real-time face detection system not only implies a system capable of analyzing video streams, but also naturally leads onto the solution to the problems of extremely constraint testing environments. Analyzing a video sequence is the current challenge since faces are constantly in dynamic motion, presenting many different possible rotational and illumination conditions. While solutions to the task of face detection have been presented, detection performances of many systems are heavily dependent upon a strictly constrained environment. The problem of detecting faces under gross variations remains largely uncovered. This study presents a real-time face detection system which uses an image based neural network to detect images.

  2. Lasso整脸形状回归的人脸配准算法%Lasso Based Shape Regression for Face Alignment

    Institute of Scientific and Technical Information of China (English)

    杨律; 丁守鸿; 谢志峰; 马利庄

    2015-01-01

    人脸配准是人脸识别、美化和面部表情分析等人脸相关应用的重要组成部分,这些应用通过人脸配准以精准定位人脸五官及面部轮廓特征点。在整脸形状回归的人脸配准框架基础上,使用 Lasso 回归来解决人脸配准问题,提出基于 Lasso 的整脸回归人脸配准算法。首先对人脸配准过程中的回归系数施加 L1模惩罚,以在不牺牲效果的基础上减少模型大小;然后提出人脸变换比例调整方法,在回归过程中使用人脸变换比例对特征点位置进行调整,用于解决小规模样本条件下不同尺度样本相互干扰的问题。在相关数据集上的实验结果表明,该算法配准精确度高,可以达到实时的速度,且适用于不同姿态下的人脸配准问题。%Face alignment focuses on the problem for localizing facial landmarks and it is an important topic of face recognition, beautification and facial expression analysis etc. Based on Explicit Shape Regression (ESR) framework, we proposed a face alignment algorithm using Lasso regression by adding aL1 norm con-straint on the model parameters to reduce the size of shape model while maintaining the resultant perform-ance. Meanwhile, a face ratio transformation method is proposed by using the face ratio to adjust the estima-tion result of face landmarks. The method can be used to solve the problem of mutual influence among various training samples in different scales. Experimental results show that the overall system performs well in related dataset and it can run in real-time and be insensitive to human faces in multiple poses.

  3. Modelling the constraints on consanguineous marriage when fertility declines

    Directory of Open Access Journals (Sweden)

    Bilal Barakat

    2014-01-01

    Full Text Available Background: Consanguinity - or marriage between close blood relatives, in particular first cousins - is widely practised and even socially encouraged in many countries. However, in the face of fertility transition where the number of cousins eligible to marry declines, how might such constraints on consanguinity develop in the future? Objective: Numerous studies have stated that the practice cannot continue at present levels and in ist present form in the face of fertility transition. However, the future impact of fertility transition on availability of cousins to marry has not yet been quantified. Methods: We perform a simulation exercise using past and projected net reproduction rates (NRRs derived from the UN. We calculate the average number of cousins of the opposite sex as a function of the average number of children, the average probability of an individual having at least one eligible paternal cousin of the opposite sex, and conclude with an examination of constraints on consanguineous marriage in selected countries under different fertility assumptions. Results: Current and projected fertility levels in Middle Eastern countries will create challenging constraints on the custom once today's birth cohorts reach marriageable age. Conclusions: Either consanguinity prevalence will diminish significantly, or the institution will be forced to adapt by becoming more coercive in the face of reduced choice or at the expense of other social preferences (such as for an older groom wedding a younger bride. Fertility decline affects prospects for social change not only through its well-known consequences for mothers but also through shaping marriage conditions for the next generation.

  4. Non-face-to-face physical activity interventions in older adults: a systematic review.

    Science.gov (United States)

    Müller, Andre Matthias; Khoo, Selina

    2014-03-10

    Physical activity is effective in preventing chronic diseases, increasing quality of life and promoting general health in older adults, but most older adults are not sufficiently active to gain those benefits. A novel and economically viable way to promote physical activity in older adults is through non-face-to-face interventions. These are conducted with reduced or no in-person interaction between intervention provider and program participants. The aim of this review was to summarize the scientific literature on non-face-to-face physical activity interventions targeting healthy, community dwelling older adults (≥ 50 years). A systematic search in six databases was conducted by combining multiple key words of the three main search categories "physical activity", "media" and "older adults". The search was restricted to English language articles published between 1st January 2000 and 31st May 2013. Reference lists of relevant articles were screened for additional publications. Seventeen articles describing sixteen non-face-to-face physical activity interventions were included in the review. All studies were conducted in developed countries, and eleven were randomized controlled trials. Sample size ranged from 31 to 2503 participants, and 13 studies included 60% or more women. Interventions were most frequently delivered via print materials and phone (n=11), compared to internet (n=3) and other media (n=2). Every intervention was theoretically framed with the Social Cognitive Theory (n=10) and the Transtheoretical Model of Behavior Change (n=6) applied mostly. Individual tailoring was reported in 15 studies. Physical activity levels were self-assessed in all studies. Fourteen studies reported significant increase in physical activity. Eight out of nine studies conducted post-intervention follow-up analysis found that physical activity was maintained over a longer time. In the six studies where intervention dose was assessed the results varied considerably. One

  5. Active constraints selection based semi-supervised dimensionality in ensemble subspaces

    Institute of Scientific and Technical Information of China (English)

    Jie Zeng; Wei Nie; Yong Zhang

    2015-01-01

    Semi-supervised dimensionality reduction (SSDR) has attracted an increasing amount of attention in this big-data era. Many algorithms have been developed with a smal number of pairwise constraints to achieve performances comparable to those of ful y supervised methods. However, one chal enging problem with semi-supervised approaches is the appropriate choice of the constraint set, including the cardinality and the composition of the constraint set, which to a large extent, affects the performance of the resulting algorithm. In this work, we address the problem by incorporating ensemble subspace and active learning into dimen-sionality reduction and propose a new algorithm, termed as global and local scatter based SSDR with active pairwise constraints selection in ensemble subspaces (SSGL-ESA). Unlike traditional methods that select the supervised information in one subspace, we pick up pairwise constraints in ensemble subspace, where a novel active learning algorithm is designed with both exploration and filtering to generate informative pairwise constraints. The auto-matic constraint selection approach proposed in this paper can be generalized to be used with al constraint-based semi-supervised learning algorithms. Comparative experiments are conducted on two face database and the results validate the effectiveness of the proposed method.

  6. IMPLEMENTASI REFERENTIAL INTEGRITY CONSTRAINT PADA MICROSOFT ACCESS DALAM UPAYA MEMELIHARA KONSISTENSI DATA

    Directory of Open Access Journals (Sweden)

    Oviliani Yenty Yuliana

    2001-01-01

    Full Text Available Data is business asset that should be safeguarded and maintained. Business data is recorded in a table/relation. Because inconeet relation structure could produce any modification anomaly, this relation should be normalized. Data modification in normalized relation will face referential integrity constraint problem. This problem could make inconsistent data and wrong information. Referential integrity constraint depends on minimum relationship cardinality. The trial and implementation of referential integrity constraint is taken on Microsoft Access. Abstract in Bahasa Indonesia : Data adalah asset perusahaan yang harus dijaga dan dipelihara. Data perusahaan dicatat pada tabel/relation. Struktur relation yang kurang baik dapat mengakibatkan modification anomaly, sehingga relation tersebut harus di-normalisasi. Modifikasi data pada relation yang sudah di-normalisasi akan menghadapi masalah referential integrity constraint. Masalah tersebut menyebabkan data tidak konsisten dan menghasilkan informasi yang salah. Referential integrity constraint tergantung pada minimum relationship cardinality. Penulis mengimplementasikan dan menguji coba referential integrity constraint pada Microsoft Access. Kata kunci: modification anomaly, normalization, referential integrity constraint, relationship cardinality constraint.

  7. Institutional constraints on alternative water for energy: a guidebook for regional assessments

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    Basic information is presented about the legal, political, and social constraints faced by energy developers in the acquisition of water from underground, irrigation return flow, municipal waste, and saline sources. It is a guide to those institutional constraints which are general and pronounced enough to be important for regional assessments. First, attention was focused on the acquisition phase of the water use cycle. Second, constraints were analyzed primarily from a regional, rather than state-by-state, perspective. Emphasis was placed generally on the West - particularly the synfuel-rich Rocky Mountain states, the East, and Mid-West, in that order. Alaska and Hawaii were not surveyed. Third, the study focuses on the constraints associated with groundwater, municipal waste, irrigation return flow, and sea water, in that order. The phrase, institutional constraints, as used in the study, means legal, social, economic, and political restrictions, requirements, circumstances, or conditions that must be anticipated or responded to in order to acquire water for energy development. The study focuses primarily on legal constraints and secondarily on political constraints, because they tend to encompass or reflect other forms of institutional constraints.

  8. "Starting from Ground Zero:" Constraints and Experiences of Adult Women Returning to College

    Science.gov (United States)

    Deutsch, Nancy L.; Schmertz, Barbara

    2011-01-01

    Women adult students face particular constraints when pursuing degrees. This paper uses focus group data to explore the educational pathways, barriers, and supports of women students. Women's educations are shaped by personal and structural gendered forces, including family, economic, and workplace issues. Women report conflict over short-term…

  9. Banking Competition and Soft Budget Constraints: How Market Power can Threaten Discipline in Lending

    NARCIS (Netherlands)

    Arping, S.

    2012-01-01

    n imperfectly competitive credit markets, banks can face a tradeoff between exploiting their market power and enforcing hard budget constraints. As market power rises, banks eventually find it too costly to discipline underperforming borrowers by stopping their projects. Lending relationships become

  10. Forensic Face Recognition: A Survey

    NARCIS (Netherlands)

    Ali, Tauseef; Veldhuis, Raymond; Spreeuwers, Luuk

    2010-01-01

    Beside a few papers which focus on the forensic aspects of automatic face recognition, there is not much published about it in contrast to the literature on developing new techniques and methodologies for biometric face recognition. In this report, we review forensic facial identification which is t

  11. Age-invariant face recognition.

    Science.gov (United States)

    Park, Unsang; Tong, Yiying; Jain, Anil K

    2010-05-01

    One of the challenges in automatic face recognition is to achieve temporal invariance. In other words, the goal is to come up with a representation and matching scheme that is robust to changes due to facial aging. Facial aging is a complex process that affects both the 3D shape of the face and its texture (e.g., wrinkles). These shape and texture changes degrade the performance of automatic face recognition systems. However, facial aging has not received substantial attention compared to other facial variations due to pose, lighting, and expression. We propose a 3D aging modeling technique and show how it can be used to compensate for the age variations to improve the face recognition performance. The aging modeling technique adapts view-invariant 3D face models to the given 2D face aging database. The proposed approach is evaluated on three different databases (i.g., FG-NET, MORPH, and BROWNS) using FaceVACS, a state-of-the-art commercial face recognition engine.

  12. Newborns' Mooney-Face Perception

    Science.gov (United States)

    Leo, Irene; Simion, Francesca

    2009-01-01

    The aim of this study is to investigate whether newborns detect a face on the basis of a Gestalt representation based on first-order relational information (i.e., the basic arrangement of face features) by using Mooney stimuli. The incomplete 2-tone Mooney stimuli were used because they preclude focusing both on the local features (i.e., the fine…

  13. PrimeFaces beginner's guide

    CERN Document Server

    Reddy, K Siva Prasad

    2013-01-01

    A guide for beginner's with step-by-step instructions and an easy-to-follow approach.PrimeFaces Beginners Guide is a simple and effective guide for beginners, wanting to learn and implement PrimeFaces in their JSF-based applications. Some basic JSF and jQuery skills are required before you start working through the book.

  14. Parallel Processing in Face Perception

    Science.gov (United States)

    Martens, Ulla; Leuthold, Hartmut; Schweinberger, Stefan R.

    2010-01-01

    The authors examined face perception models with regard to the functional and temporal organization of facial identity and expression analysis. Participants performed a manual 2-choice go/no-go task to classify faces, where response hand depended on facial familiarity (famous vs. unfamiliar) and response execution depended on facial expression…

  15. Side-View Face Recognition

    NARCIS (Netherlands)

    Santemiz, Pinar; Spreeuwers, Luuk J.; Veldhuis, Raymond N.J.; Biggelaar , van den Olivier

    2011-01-01

    As a widely used biometrics, face recognition has many advantages such as being non-intrusive, natural and passive. On the other hand, in real-life scenarios with uncontrolled environment, pose variation up to side-view positions makes face recognition a challenging work. In this paper we discuss th

  16. Modeling Social Perception of Faces

    NARCIS (Netherlands)

    Todorov, A.T.; Oosterhof, N.N.

    2011-01-01

    The face is our primary source of visual information for identifying people and reading their emotional and mental states. With the exception of prosopagnosics (who are unable to recognize faces) and those suffering from such disorders of social cognition as autism, people are extremely adept at the

  17. The Importance of Formalizing Computational Models of Face Adaptation Aftereffects

    Science.gov (United States)

    Ross, David A.; Palmeri, Thomas J.

    2016-01-01

    Face adaptation is widely used as a means to probe the neural representations that support face recognition. While the theories that relate face adaptation to behavioral aftereffects may seem conceptually simple, our work has shown that testing computational instantiations of these theories can lead to unexpected results. Instantiating a model of face adaptation not only requires specifying how faces are represented and how adaptation shapes those representations but also specifying how decisions are made, translating hidden representational states into observed responses. Considering the high-dimensionality of face representations, the parallel activation of multiple representations, and the non-linearity of activation functions and decision mechanisms, intuitions alone are unlikely to succeed. If the goal is to understand mechanism, not simply to examine the boundaries of a behavioral phenomenon or correlate behavior with brain activity, then formal computational modeling must be a component of theory testing. To illustrate, we highlight our recent computational modeling of face adaptation aftereffects and discuss how models can be used to understand the mechanisms by which faces are recognized. PMID:27378960

  18. Neural correlates of recognition memory for emotional faces and scenes.

    Science.gov (United States)

    Keightley, Michelle L; Chiew, Kimberly S; Anderson, John A E; Grady, Cheryl L

    2011-01-01

    We examined the influence of emotional valence and type of item to be remembered on brain activity during recognition, using faces and scenes. We used multivariate analyses of event-related fMRI data to identify whole-brain patterns, or networks of activity. Participants demonstrated better recognition for scenes vs faces and for negative vs neutral and positive items. Activity was increased in extrastriate cortex and inferior frontal gyri for emotional scenes, relative to neutral scenes and all face types. Increased activity in these regions also was seen for negative faces relative to positive faces. Correct recognition of negative faces and scenes (hits vs correct rejections) was associated with increased activity in amygdala, hippocampus, extrastriate, frontal and parietal cortices. Activity specific to correctly recognized emotional faces, but not scenes, was found in sensorimotor areas and rostral prefrontal cortex. These results suggest that emotional valence and type of visual stimulus both modulate brain activity at recognition, and influence multiple networks mediating visual, memory and emotion processing. The contextual information in emotional scenes may facilitate memory via additional visual processing, whereas memory for emotional faces may rely more on cognitive control mediated by rostrolateral prefrontal regions.

  19. Priming with threatening faces modulates the self-face advantage by enhancing the other-face processing rather than suppressing the self-face processing.

    Science.gov (United States)

    Guan, Lili; Qi, Mingming; Li, Haijiang; Hitchman, Glenn; Yang, Juan; Liu, Yijun

    2015-05-22

    Social emotional information influences self-processing in everyday activities, but few researchers have investigated this process. The current ERP study adopted a prime paradigm to investigate how socially threatening faces impact on the self-face processing advantage. After being primed with emotional faces (happy, angry or neutral), participants judged whether the target face (self, friend, and stranger) was familiar or unfamiliar. Results showed an interaction effect between the prime face and the target face at posterior P3, suggesting that after priming with happy and neutral faces, self-faces elicited larger P3 amplitudes than friend-faces and stranger-faces; however, after priming with angry faces, the P3 amplitudes were not significantly different between self-face and friend-face. Moreover, the P3 amplitudes of self-faces did not differ between priming with angry and neutral faces; however, the P3 amplitude of both friend-faces and stranger-faces showed enhanced responses after priming with angry faces compared to priming with neutral faces. We suggest that the self-face processing advantage (self vs. friend) could be weakened by priming with threatening faces, through enhancement of the other-faces processing rather than suppression of self-faces processing in angry vs. neutral face prime.

  20. Emotion-independent face recognition

    Science.gov (United States)

    De Silva, Liyanage C.; Esther, Kho G. P.

    2000-12-01

    Current face recognition techniques tend to work well when recognizing faces under small variations in lighting, facial expression and pose, but deteriorate under more extreme conditions. In this paper, a face recognition system to recognize faces of known individuals, despite variations in facial expression due to different emotions, is developed. The eigenface approach is used for feature extraction. Classification methods include Euclidean distance, back propagation neural network and generalized regression neural network. These methods yield 100% recognition accuracy when the training database is representative, containing one image representing the peak expression for each emotion of each person apart from the neutral expression. The feature vectors used for comparison in the Euclidean distance method and for training the neural network must be all the feature vectors of the training set. These results are obtained for a face database consisting of only four persons.

  1. Effective indexing for face recognition

    Science.gov (United States)

    Sochenkov, I.; Sochenkova, A.; Vokhmintsev, A.; Makovetskii, A.; Melnikov, A.

    2016-09-01

    Face recognition is one of the most important tasks in computer vision and pattern recognition. Face recognition is useful for security systems to provide safety. In some situations it is necessary to identify the person among many others. In this case this work presents new approach in data indexing, which provides fast retrieval in big image collections. Data indexing in this research consists of five steps. First, we detect the area containing face, second we align face, and then we detect areas containing eyes and eyebrows, nose, mouth. After that we find key points of each area using different descriptors and finally index these descriptors with help of quantization procedure. The experimental analysis of this method is performed. This paper shows that performing method has results at the level of state-of-the-art face recognition methods, but it is also gives results fast that is important for the systems that provide safety.

  2. Genetic specificity of face recognition.

    Science.gov (United States)

    Shakeshaft, Nicholas G; Plomin, Robert

    2015-10-13

    Specific cognitive abilities in diverse domains are typically found to be highly heritable and substantially correlated with general cognitive ability (g), both phenotypically and genetically. Recent twin studies have found the ability to memorize and recognize faces to be an exception, being similarly heritable but phenotypically substantially uncorrelated both with g and with general object recognition. However, the genetic relationships between face recognition and other abilities (the extent to which they share a common genetic etiology) cannot be determined from phenotypic associations. In this, to our knowledge, first study of the genetic associations between face recognition and other domains, 2,000 18- and 19-year-old United Kingdom twins completed tests assessing their face recognition, object recognition, and general cognitive abilities. Results confirmed the substantial heritability of face recognition (61%), and multivariate genetic analyses found that most of this genetic influence is unique and not shared with other cognitive abilities.

  3. Learning faces: similar comparator faces do not improve performance.

    Directory of Open Access Journals (Sweden)

    Scott P Jones

    Full Text Available Recent evidence indicates that comparison of two similar faces can aid subsequent discrimination between them. However, the fact that discrimination between two faces is facilitated by comparing them directly does not demonstrate that comparison produces a general improvement in the processing of faces. It remains an open question whether the opportunity to compare a "target" face to similar faces can facilitate the discrimination of the exposed target face from other nonexposed faces. In Experiment 1, selection of a target face from an array of novel foils was not facilitated by intermixed exposure to the target and comparators of the same sex. Experiment 2 also found no advantage for similar comparators (morphed towards the target over unmorphed same sex comparators, or over repeated target exposure alone. But all repeated exposure conditions produced better performance than a single brief presentation of the target. Experiment 3 again demonstrated that repeated exposure produced equivalent learning in same sex and different sex comparator conditions, and also showed that increasing the number of same sex or different sex comparators failed to improve identification. In all three experiments, exposure to a target alongside similar comparators failed to support selection of the target from novel test stimuli to a greater degree than exposure alongside dissimilar comparators or repeated target exposure alone. The current results suggest that the facilitatory effects of comparison during exposure may be limited to improving discrimination between exposed stimuli, and thus our results do not support the idea that providing the opportunity for comparison is a practical means for improving face identification.

  4. Creativity from Constraints in Engineering Design

    DEFF Research Database (Denmark)

    Onarheim, Balder

    2012-01-01

    This paper investigates the role of constraints in limiting and enhancing creativity in engineering design. Based on a review of literature relating constraints to creativity, the paper presents a longitudinal participatory study from Coloplast A/S, a major international producer of disposable......, removal, introducing and revising. Constraints introduced late in a project contributed to the generation of new solutions to old problems, and existing solutions were creatively adopted to satisfy new constraints. This paper recommends creative constraint-handling strategies, as well as identifying...... potential directions for future research on the relationship between creativity and constraints...

  5. Robust Face Recognition Via Gabor Feature and Sparse Representation

    Directory of Open Access Journals (Sweden)

    Hao Yu-Juan

    2016-01-01

    Full Text Available Sparse representation based on compressed sensing theory has been widely used in the field of face recognition, and has achieved good recognition results. but the face feature extraction based on sparse representation is too simple, and the sparse coefficient is not sparse. In this paper, we improve the classification algorithm based on the fusion of sparse representation and Gabor feature, and then improved algorithm for Gabor feature which overcomes the problem of large dimension of the vector dimension, reduces the computation and storage cost, and enhances the robustness of the algorithm to the changes of the environment.The classification efficiency of sparse representation is determined by the collaborative representation,we simplify the sparse constraint based on L1 norm to the least square constraint, which makes the sparse coefficients both positive and reduce the complexity of the algorithm. Experimental results show that the proposed method is robust to illumination, facial expression and pose variations of face recognition, and the recognition rate of the algorithm is improved.

  6. Training of familiar face recognition and visual scan paths for faces in a child with congenital prosopagnosia.

    Science.gov (United States)

    Schmalzl, Laura; Palermo, Romina; Green, Melissa; Brunsdon, Ruth; Coltheart, Max

    2008-07-01

    In the current report we describe a successful training study aimed at improving recognition of a set of familiar face photographs in K., a 4-year-old girl with congenital prosopagnosia (CP). A detailed assessment of K.'s face-processing skills showed a deficit in structural encoding, most pronounced in the processing of facial features within the face. In addition, eye movement recordings revealed that K.'s scan paths for faces were characterized by a large percentage of fixations directed to areas outside the internal core features (i.e., eyes, nose, and mouth), in particular by poor attendance to the eye region. Following multiple baseline assessments, training focused on teaching K. to reliably recognize a set of familiar face photographs by directing visual attention to specific characteristics of the internal features of each face. The training significantly improved K.'s ability to recognize the target faces, with her performance being flawless immediately after training as well as at a follow-up assessment 1 month later. In addition, eye movement recordings following training showed a significant change in K.'s scan paths, with a significant increase in the percentage of fixations directed to the internal features, particularly the eye region. Encouragingly, not only was the change in scan paths observed for the set of familiar trained faces, but it generalized to a set of faces that was not presented during training. In addition to documenting significant training effects, our study raises the intriguing question of whether abnormal scan paths for faces may be a common factor underlying face recognition impairments in childhood CP, an issue that has not been explored so far.

  7. Modeling human dynamics of face-to-face interaction networks

    CERN Document Server

    Starnini, Michele; Pastor-Satorras, Romualdo

    2013-01-01

    Face-to-face interaction networks describe social interactions in human gatherings, and are the substrate for processes such as epidemic spreading and gossip propagation. The bursty nature of human behavior characterizes many aspects of empirical data, such as the distribution of conversation lengths, of conversations per person, or of inter-conversation times. Despite several recent attempts, a general theoretical understanding of the global picture emerging from data is still lacking. Here we present a simple model that reproduces quantitatively most of the relevant features of empirical face-to-face interaction networks. The model describes agents which perform a random walk in a two dimensional space and are characterized by an attractiveness whose effect is to slow down the motion of people around them. The proposed framework sheds light on the dynamics of human interactions and can improve the modeling of dynamical processes taking place on the ensuing dynamical social networks.

  8. Temporal networks of face-to-face human interactions

    CERN Document Server

    Barrat, Alain

    2013-01-01

    The ever increasing adoption of mobile technologies and ubiquitous services allows to sense human behavior at unprecedented levels of details and scale. Wearable sensors are opening up a new window on human mobility and proximity at the finest resolution of face-to-face proximity. As a consequence, empirical data describing social and behavioral networks are acquiring a longitudinal dimension that brings forth new challenges for analysis and modeling. Here we review recent work on the representation and analysis of temporal networks of face-to-face human proximity, based on large-scale datasets collected in the context of the SocioPatterns collaboration. We show that the raw behavioral data can be studied at various levels of coarse-graining, which turn out to be complementary to one another, with each level exposing different features of the underlying system. We briefly review a generative model of temporal contact networks that reproduces some statistical observables. Then, we shift our focus from surface ...

  9. Ethical considerations in face transplantation.

    Science.gov (United States)

    Brown, Charles S; Gander, Brian; Cunningham, Michael; Furr, Allen; Vasilic, Dalibor; Wiggins, Osborne; Banis, Joseph C; Vossen, Marieke; Maldonado, Claudio; Perez-Abadia, Gustavo; Barker, John H

    2007-10-01

    Human face transplantation is now a clinical reality. The surgical techniques necessary to perform these procedures have been used routinely in reconstructive microsurgery for many years. From an immunological standpoint since face and hand contain mostly the same tissues it is reasonable to assume that the same immunosuppressive regimen found to be effective in human hand transplants should also work in face transplantation. It is the ethical issues associated with the risks and benefits of performing facial transplantation that have posed the greatest challenges leading up to performing this new procedure. In this editorial, we will review some of the main events that have led to the recently performed human face transplants, specifically focusing on the key ethical issues at the center of this debate. We will discuss how the research and clinical experience in human hand transplantation laid the foundation for performing face transplantation and describe the research and the ethical guidelines upon which a team at the University of Louisville based their position "to move ahead" in spite of much criticism. Finally we will outline some of the key arguments against face transplantation, and conclude with a discussion on what comes next now that the first human face transplants have been performed.

  10. Multithread Face Recognition in Cloud

    Directory of Open Access Journals (Sweden)

    Dakshina Ranjan Kisku

    2016-01-01

    Full Text Available Faces are highly challenging and dynamic objects that are employed as biometrics evidence in identity verification. Recently, biometrics systems have proven to be an essential security tools, in which bulk matching of enrolled people and watch lists is performed every day. To facilitate this process, organizations with large computing facilities need to maintain these facilities. To minimize the burden of maintaining these costly facilities for enrollment and recognition, multinational companies can transfer this responsibility to third-party vendors who can maintain cloud computing infrastructures for recognition. In this paper, we showcase cloud computing-enabled face recognition, which utilizes PCA-characterized face instances and reduces the number of invariant SIFT points that are extracted from each face. To achieve high interclass and low intraclass variances, a set of six PCA-characterized face instances is computed on columns of each face image by varying the number of principal components. Extracted SIFT keypoints are fused using sum and max fusion rules. A novel cohort selection technique is applied to increase the total performance. The proposed protomodel is tested on BioID and FEI face databases, and the efficacy of the system is proven based on the obtained results. We also compare the proposed method with other well-known methods.

  11. Efficient multi-site data movement using constraint programming for data hungry science

    Science.gov (United States)

    Zerola, Michal; Lauret, Jérôme; Barták, Roman; Šumbera, Michal

    2010-04-01

    For the past decade, HENP experiments have been heading towards a distributed computing model in an effort to concurrently process tasks over enormous data sets that have been increasing in size as a function of time. In order to optimize all available resources (geographically spread) and minimize the processing time, it is necessary to face also the question of efficient data transfers and placements. A key question is whether the time penalty for moving the data to the computational resources is worth the presumed gain. Onward to the truly distributed task scheduling we present the technique using a Constraint Programming (CP) approach. The CP technique schedules data transfers from multiple resources considering all available paths of diverse characteristic (capacity, sharing and storage) having minimum user's waiting time as an objective. We introduce a model for planning data transfers to a single destination (data transfer) as well as its extension for an optimal data set spreading strategy (data placement). Several enhancements for a solver of the CP model will be shown, leading to a faster schedule computation time using symmetry breaking, branch cutting, well studied principles from job-shop scheduling field and several heuristics. Finally, we will present the design and implementation of a corner-stone application aimed at moving datasets according to the schedule. Results will include comparison of performance and trade-off between CP techniques and a Peer-2-Peer model from simulation framework as well as the real case scenario taken from a practical usage of a CP scheduler.

  12. Self-Imposed Creativity Constraints

    DEFF Research Database (Denmark)

    Biskjaer, Michael Mose

    2013-01-01

    . As the majority of work in creativity research originates from psychology, the dissertation shows how the humanities – given their salient critical-analytical reflection and high concept awareness – can contribute new types of studies to creativity research, which, despite its blossoming as a field, is becoming...... increasingly fragmented and in need of new ‘big’ unifying questions. Hence the designation of the dissertation’s research approach. The four papers serve a dual purpose. They are contributions in their own right, and they provide partial answers to the overall research question. In this respect, the concept...... of the current dispersed studies on constraints in creativity, spanning psychology, engineering, philosophy, design, and aesthetics. (2) Definitions, concepts, and models of self-imposed creativity constraints for analytical application within and across creative domains, including the 6i model for demonstrating...

  13. Observational Constraints on Exponential Gravity

    CERN Document Server

    Yang, Louis; Luo, Ling-Wei; Geng, Chao-Qiang

    2010-01-01

    We study the observational constraints on the exponential gravity model of f(R)=-beta*Rs(1-e^(-R/Rs)). We use the latest observational data including Supernova Cosmology Project (SCP) Union2 compilation, Two-Degree Field Galaxy Redshift Survey (2dFGRS), Sloan Digital Sky Survey Data Release 7 (SDSS DR7) and Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP7) in our analysis. From these observations, we obtain a lower bound on the model parameter beta at 1.27 (95% CL) but no appreciable upper bound. The constraint on the present matter density parameter is 0.245< Omega_m^0<0.311 (95% CL). We also find out the best-fit value of model parameters on several cases.

  14. A Compendium of Chameleon Constraints

    CERN Document Server

    Burrage, Clare

    2016-01-01

    The chameleon model is a scalar field theory with a screening mechanism that explains how a cosmologically relevant light scalar can avoid the constraints of intra-solar-system searches for fifth-forces. The chameleon is a popular dark energy candidate and also arises in $f(R)$ theories of gravity. Whilst the chameleon is designed to avoid historical searches for fifth-forces it is not unobservable and much effort has gone into identifying the best observables and experiments to detect it. These results are not always presented for the same models or in the same language, a particular problem when comparing astrophysical and laboratory searches making it difficult to understand what regions of parameter space remain. Here we present combined constraints on the chameleon model from astrophysical and laboratory searches for the first time and identify the remaining windows of parameter space. We discuss the implications for cosmological chameleon searches and future small-scale probes.

  15. Integral Constraints and MHD Stability

    Science.gov (United States)

    Jensen, T. H.

    2003-10-01

    Determining stability of a plasma in MHD equilibrium, energetically isolated by a conducting wall, requires an assumption on what governs the dynamics of the plasma. One example is the assumption that the plasma obeys ideal MHD, leading to the well known ``δ W" criteria [I. Bernstein, et al., Proc. Roy. Soc. London A244, 17 (1958)]. A radically different approach was used by Taylor [J.B. Taylor, Rev. Mod. Phys. 58, 741 (1986)] in assuming that the dynamics of the plasma is restricted only by the requirement that helicity, an integral constant associated with the plasma, is conserved. The relevancy of Taylor's assumption is supported by the agreement between resulting theoretical results and experimental observations. Another integral constraint involves the canonical angular momentum of the plasma particles. One consequence of using this constraint is that tokamak plasmas have no poloidal current in agreement with some current hole tokamak observations [T.H. Jensen, Phys. Lett. A 305, 183 (2002)].

  16. A compendium of chameleon constraints

    Science.gov (United States)

    Burrage, Clare; Sakstein, Jeremy

    2016-11-01

    The chameleon model is a scalar field theory with a screening mechanism that explains how a cosmologically relevant light scalar can avoid the constraints of intra-solar-system searches for fifth-forces. The chameleon is a popular dark energy candidate and also arises in f(R) theories of gravity. Whilst the chameleon is designed to avoid historical searches for fifth-forces it is not unobservable and much effort has gone into identifying the best observables and experiments to detect it. These results are not always presented for the same models or in the same language, a particular problem when comparing astrophysical and laboratory searches making it difficult to understand what regions of parameter space remain. Here we present combined constraints on the chameleon model from astrophysical and laboratory searches for the first time and identify the remaining windows of parameter space. We discuss the implications for cosmological chameleon searches and future small-scale probes.

  17. Self-Imposed Creativity Constraints

    DEFF Research Database (Denmark)

    Biskjaer, Michael Mose

    2013-01-01

    Abstract This dissertation epitomizes three years of research guided by the research question: how can we conceptualize creative self-binding as a resource in art and design processes? Concretely, the dissertation seeks to offer insight into the puzzling observation that highly skilled creative...... practitioners sometimes freely and intentionally impose rigid rules, peculiar principles, and other kinds of creative obstructions on themselves as a means to spur momentum in the process and reach a distinctly original outcome. To investigate this the dissertation is composed of four papers (Part II) framed...... of analysis. Informed by the insight that constraints both enable and restrain creative agency, the dissertation’s main contention is that creative self- binding may profitably be conceptualized as the exercise of self-imposed creativity constraints. Thus, the dissertation marks an analytical move from vague...

  18. Part-based set matching for face recognition in surveillance

    Science.gov (United States)

    Zheng, Fei; Wang, Guijin; Lin, Xinggang

    2013-12-01

    Face recognition in surveillance is a hot topic in computer vision due to the strong demand for public security and remains a challenging task owing to large variations in viewpoint and illumination of cameras. In surveillance, image sets are the most natural form of input by incorporating tracking. Recent advances in set-based matching also show its great potential for exploring the feature space for face recognition by making use of multiple samples of subjects. In this paper, we propose a novel method that exploits the salient features (such as eyes, noses, mouth) in set-based matching. To represent image sets, we adopt the affine hull model, which can general unseen appearances in the form of affine combinations of sample images. In our proposal, a robust part detector is first used to find four salient parts for each face image: two eyes, nose, and mouth. For each part, we construct an affine hull model by using the local binary pattern histograms of multiple samples of the part. We also construct an affine model for the whole face region. Then, we find the closest distance between the corresponding affine hull models to measure the similarity between parts/face regions, and a weighting scheme is introduced to combine the five distances (four parts and the whole face region) to obtain the final distance between two subjects. In the recognition phase, a nearest neighbor classifier is used. Experiments on the public ChokePoint dataset and our dataset demonstrate the superior performance of our method.

  19. Deepening Contractions and Collateral Constraints

    DEFF Research Database (Denmark)

    Jensen, Henrik; Ravn, Søren Hove; Santoro, Emiliano

    on the differential impact that occasionally non-binding constraints exert on the shape of expansions and contractions, we are also able to reconcile a more negatively skewed business cycle with a moderation in its volatility. Finally, our model can account for an intrinsic feature of economic downturns preceded...... by private credit build-ups: Financially driven expansions lead to deeper contractions, as compared to equally-sized non-financial expansions....

  20. Managing Restaurant Tables using Constraints

    Science.gov (United States)

    Vidotto, Alfio; Brown, Kenneth N.; Beck, J. Christopher

    Restaurant table management can have significant impact on both profitability and the customer experience. The core of the issue is a complex dynamic combinatorial problem. We show how to model the problem as constraint satisfaction, with extensions which generate flexible seating plans and which maintain stability when changes occur. We describe an implemented system which provides advice to users in real time. The system is currently being evaluated in a restaurant environment.

  1. Causality constraints on TMD PDF

    CERN Document Server

    Efremov, A V

    2013-01-01

    In this short note, we discuss constraints on the transverse momentum dependent factorization formulae coming from the causality properties for the hadronic tensor. We show that the range of definition of the TMD PDFs in the transverse coordinate plane is wider that it is allowed by the causality. It indicates the presents of the large compensating corrections for the TMD PDF factorization theorem and/or overestimation of the transverse component dependence of TMD PDF.

  2. Expressing Preferences using Preference Set Constraint Atoms

    CERN Document Server

    Brik, Alex

    2012-01-01

    This paper introduces an extension of Answer Set Programming called Preference Set Constraint Programming which is a convenient and general formalism to reason with preferences. PSC programming extends Set Constraint Programming introduced by Marek and Remmel (Marek and Remmel 2004) by introducing two types of preference set constraint atoms, measure preference set constraint atoms and pre-ordered preference set constraint atoms, which are extensions of set constraint atoms. We show that the question of whether a PSC program has a preferred stable model is CoNP-complete. We give examples of the uses of the preference set constraint atoms and show that Answer Set Optimization (Brewka, Niemel\\"a, and Truszczynski 2003) and General Preference (Son and Pontelli 2006) can be expressed using preference set constraint atoms.

  3. Relaxations of semiring constraint satisfaction problems

    CSIR Research Space (South Africa)

    Leenen, L

    2007-03-01

    Full Text Available The Semiring Constraint Satisfaction Problem (SCSP) framework is a popular approach for the representation of partial constraint satisfaction problems. In this framework preferences can be associated with tuples of values of the variable domains...

  4. A Hybrid method of face detection based on Feature Extraction using PIFR and Feature Optimization using TLBO

    Directory of Open Access Journals (Sweden)

    Kapil Verma

    2016-01-01

    Full Text Available In this paper we proposed a face detection method based on feature selection and feature optimization. Now in current research trend of biometric security used the process of feature optimization for better improvement of face detection technique. Basically our face consists of three types of feature such as skin color, texture and shape and size of face. The most important feature of face is skin color and texture of face. In this detection technique used texture feature of face image. For the texture extraction of image face used partial feature extraction function, these function is most promising shape feature analysis. For the selection of feature and optimization of feature used multi-objective TLBO. TLBO algorithm is population based searching technique and defines two constraints function for the process of selection and optimization. The proposed algorithm of face detection based on feature selection and feature optimization process. Initially used face image data base and passes through partial feature extractor function and these transform function gives a texture feature of face image. For the evaluation of performance our proposed algorithm implemented in MATLAB 7.8.0 software and face image used provided by Google face image database. For numerical analysis of result used hit and miss ratio. Our empirical evaluation of result shows better prediction result in compression of PIFR method of face detection.

  5. Infrared Constraint on Ultraviolet Theories

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Yuhsin [Cornell Univ., Ithaca, NY (United States)

    2012-08-01

    While our current paradigm of particle physics, the Standard Model (SM), has been extremely successful at explaining experiments, it is theoretically incomplete and must be embedded into a larger framework. In this thesis, we review the main motivations for theories beyond the SM (BSM) and the ways such theories can be constrained using low energy physics. The hierarchy problem, neutrino mass and the existence of dark matter (DM) are the main reasons why the SM is incomplete . Two of the most plausible theories that may solve the hierarchy problem are the Randall-Sundrum (RS) models and supersymmetry (SUSY). RS models usually suffer from strong flavor constraints, while SUSY models produce extra degrees of freedom that need to be hidden from current experiments. To show the importance of infrared (IR) physics constraints, we discuss the flavor bounds on the anarchic RS model in both the lepton and quark sectors. For SUSY models, we discuss the difficulties in obtaining a phenomenologically allowed gaugino mass, its relation to R-symmetry breaking, and how to build a model that avoids this problem. For the neutrino mass problem, we discuss the idea of generating small neutrino masses using compositeness. By requiring successful leptogenesis and the existence of warm dark matter (WDM), we can set various constraints on the hidden composite sector. Finally, to give an example of model independent bounds from collider experiments, we show how to constrain the DM–SM particle interactions using collider results with an effective coupling description.

  6. Closure constraints for hyperbolic tetrahedra

    CERN Document Server

    Charles, Christoph

    2015-01-01

    We investigate the generalization of loop gravity's twisted geometries to a q-deformed gauge group. In the standard undeformed case, loop gravity is a formulation of general relativity as a diffeomorphism-invariant SU(2) gauge theory. Its classical states are graphs provided with algebraic data. In particular closure constraints at every node of the graph ensure their interpretation as twisted geometries. Dual to each node, one has a polyhedron embedded in flat space R^3. One then glues them allowing for both curvature and torsion. It was recently conjectured that q-deforming the gauge group SU(2) would allow to account for a non-vanishing cosmological constant Lambda, and in particular that deforming the loop gravity phase space with real parameter q>0 would lead to a generalization of twisted geometries to a hyperbolic curvature. Following this insight, we look for generalization of the closure constraints to the hyperbolic case. In particular, we introduce two new closure constraints for hyperbolic tetrahe...

  7. Updating neutrino magnetic moment constraints

    Directory of Open Access Journals (Sweden)

    B.C. Cañas

    2016-02-01

    Full Text Available In this paper we provide an updated analysis of the neutrino magnetic moments (NMMs, discussing both the constraints on the magnitudes of the three transition moments Λi and the role of the CP violating phases present both in the mixing matrix and in the NMM matrix. The scattering of solar neutrinos off electrons in Borexino provides the most stringent restrictions, due to its robust statistics and the low energies observed, below 1 MeV. Our new limit on the effective neutrino magnetic moment which follows from the most recent Borexino data is 3.1×10−11μB at 90% C.L. This corresponds to the individual transition magnetic moment constraints: |Λ1|≤5.6×10−11μB, |Λ2|≤4.0×10−11μB, and |Λ3|≤3.1×10−11μB (90% C.L., irrespective of any complex phase. Indeed, the incoherent admixture of neutrino mass eigenstates present in the solar flux makes Borexino insensitive to the Majorana phases present in the NMM matrix. For this reason we also provide a global analysis including the case of reactor and accelerator neutrino sources, presenting the resulting constraints for different values of the relevant CP phases. Improved reactor and accelerator neutrino experiments will be needed in order to underpin the full profile of the neutrino electromagnetic properties.

  8. Beyond the Therapeutic Hour: An Exploratory Pilot Study of Using Technology to Enhance Alliance and Engagement within Face-to-Face Psychotherapy

    Science.gov (United States)

    Richards, Penelope; Simpson, Susan

    2015-01-01

    In this paper we introduce and investigate the capacity for a novel, technologically advanced system (goACT) to enhance face-to-face psychotherapy. Specifically, we explore the capacity for goACT to enhance therapeutic alliance (TA) and engagement, and reduce distress. Using a mixed-methods, multiple-baseline design we present the first study to…

  9. Multimodal registration of the face for computer-aided maxillofacial surgery

    CERN Document Server

    Leloup, T; Payan, Y; Leloup, Thierry; Chabanas, Matthieu; Payan, Yohan

    2006-01-01

    This paper introduces a multimodal elastic registration algorithm applied to match a generic Finite Element model of the face to several patients morphologies. The method is automatic and appears to be accurate and robust. The computing time is compatible with clinical practice constraints.

  10. Geometric constraint solving with geometric transformation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper proposes two algorithms for solving geometric constraint systems. The first algorithm is for constrained systems without loops and has linear complexity. The second algorithm can solve constraint systems with loops. The latter algorithm is of quadratic complexity and is complete for constraint problems about simple polygons. The key to it is to combine the idea of graph based methods for geometric constraint solving and geometric transformations coming from rule-based methods.

  11. Ant colony optimization and constraint programming

    CERN Document Server

    Solnon, Christine

    2013-01-01

    Ant colony optimization is a metaheuristic which has been successfully applied to a wide range of combinatorial optimization problems. The author describes this metaheuristic and studies its efficiency for solving some hard combinatorial problems, with a specific focus on constraint programming. The text is organized into three parts. The first part introduces constraint programming, which provides high level features to declaratively model problems by means of constraints. It describes the main existing approaches for solving constraint satisfaction problems, including complete tree search

  12. Set Constraints and Logic Programming (Preprint)

    Science.gov (United States)

    2016-02-24

    Assoc Comput Sci Logic Springer September A Aiken D Kozen and E Wimmers Decidability of systems of set constraints with negative...Extensions of Logic Programming ELP volume of Lect Notes Articial Intell pages Springer February J Englefriet Tree... Springer September D Kozen Set constraints and logic programming abstract In JP Jouannaud editor Proc First Conf Constraints in

  13. A general treatment of dynamic integrity constraints

    NARCIS (Netherlands)

    de Brock, EO

    This paper introduces a general, set-theoretic model for expressing dynamic integrity constraints, i.e., integrity constraints on the state changes that are allowed in a given state space. In a managerial context, such dynamic integrity constraints can be seen as representations of "real world"

  14. The Ambiguous Role of Constraints in Creativity

    DEFF Research Database (Denmark)

    Biskjær, Michael Mose; Onarheim, Balder; Wiltschnig, Stefan

    2011-01-01

    The relationship between creativity and constraints is often described in the literature either in rather imprecise, general concepts or in relation to very specific domains. Cross-domain and cross-disciplinary takes on how the handling of constraints influences creative activities are rare. In t......-disciplinary research into the ambiguous role of constraints in creativity....

  15. A general treatment of dynamic integrity constraints

    NARCIS (Netherlands)

    de Brock, EO

    2000-01-01

    This paper introduces a general, set-theoretic model for expressing dynamic integrity constraints, i.e., integrity constraints on the state changes that are allowed in a given state space. In a managerial context, such dynamic integrity constraints can be seen as representations of "real world" cons

  16. Bracing Zonohedra With Special Faces

    Directory of Open Access Journals (Sweden)

    Nagy Gyula

    2015-12-01

    Full Text Available The analysis of simpler preliminary design gives useful input for more complicated three-dimensional building frame structure. A zonohedron, as a preliminary structure of design, is a convex polyhedron for which each face possesses central symmetry. We considered zonohedron as a special framework with the special assumption that the polygonal faces can be deformed in such a way that faces remain planar and centrally symmetric, moreover the length of all edges remains unchanged. Introducing some diagonal braces we got a new mechanism. This paper deals with the flexibility of this kind of mechanisms, and investigates the rigidity of the braced framework. The flexibility of the framework can be characterized by some vectors, which represent equivalence classes of the edges. A necessary and sufficient condition for the rigidity of the braced rhombic face zonohedra is posed. A real mechanical construction, based on two simple elements, provides a CAD prototype of these new mechanisms.

  17. Face Recognition using Curvelet Transform

    CERN Document Server

    Cohen, Rami

    2011-01-01

    Face recognition has been studied extensively for more than 20 years now. Since the beginning of 90s the subject has became a major issue. This technology is used in many important real-world applications, such as video surveillance, smart cards, database security, internet and intranet access. This report reviews recent two algorithms for face recognition which take advantage of a relatively new multiscale geometric analysis tool - Curvelet transform, for facial processing and feature extraction. This transform proves to be efficient especially due to its good ability to detect curves and lines, which characterize the human's face. An algorithm which is based on the two algorithms mentioned above is proposed, and its performance is evaluated on three data bases of faces: AT&T (ORL), Essex Grimace and Georgia-Tech. k-nearest neighbour (k-NN) and Support vector machine (SVM) classifiers are used, along with Principal Component Analysis (PCA) for dimensionality reduction. This algorithm shows good results, ...

  18. Face Recognition in Various Illuminations

    Directory of Open Access Journals (Sweden)

    Saurabh D. Parmar,

    2014-05-01

    Full Text Available Face Recognition (FR under various illuminations is very challenging. Normalization technique is useful for removing the dimness and shadow from the facial image which reduces the effect of illumination variations still retaining the necessary information of the face. The robust local feature extractor which is the gray-scale invariant texture called Local Binary Pattern (LBP is helpful for feature extraction. K-Nearest Neighbor classifier is utilized for the purpose of classification and to match the face images from the database. Experimental results were based on Yale-B database with three different sub categories. The proposed method has been tested to robust face recognition in various illumination conditions. Extensive experiment shows that the proposed system can achieve very encouraging performance in various illumination environments.

  19. Similarity measures for face recognition

    CERN Document Server

    Vezzetti, Enrico

    2015-01-01

    Face recognition has several applications, including security, such as (authentication and identification of device users and criminal suspects), and in medicine (corrective surgery and diagnosis). Facial recognition programs rely on algorithms that can compare and compute the similarity between two sets of images. This eBook explains some of the similarity measures used in facial recognition systems in a single volume. Readers will learn about various measures including Minkowski distances, Mahalanobis distances, Hansdorff distances, cosine-based distances, among other methods. The book also summarizes errors that may occur in face recognition methods. Computer scientists "facing face" and looking to select and test different methods of computing similarities will benefit from this book. The book is also useful tool for students undertaking computer vision courses.

  20. Covert Face Recognition without Prosopagnosia

    Directory of Open Access Journals (Sweden)

    H. D. Ellis

    1993-01-01

    Full Text Available An experiment is reported where subjects were presented with familiar or unfamiliar faces for supraliminal durations or for durations individually assessed as being below the threshold for recognition. Their electrodermal responses to each stimulus were measured and the results showed higher peak amplitude skin conductance responses for familiar than for unfamiliar faces, regardless of whether they had been displayed supraliminally or subliminally. A parallel is drawn between elevated skin conductance responses to subliminal stimuli and findings of covert recognition of familiar faces in prosopagnosic patients, some of whom show increased electrodermal activity (EDA to previously familiar faces. The supraliminal presentation data also served to replicate similar work by Tranel et al (1985. The results are considered alongside other data indicating the relation between non-conscious, “automatic” aspects of normal visual information processing and abilities which can be found to be preserved without awareness after brain injury.

  1. More Than a Pretty Face

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The various facial make up designs in the Sichuan Opera are Chinese art treasures With the flick of a wrist,the intricate patterns painted on the opera performer’s face magically shift;the audience,awed

  2. Face recognition using Krawtchouk moment

    Indian Academy of Sciences (India)

    J Sheeba Rani; D Devaraj

    2012-08-01

    Feature extraction is one of the important tasks in face recognition. Moments are widely used feature extractor due to their superior discriminatory power and geometrical invariance. Moments generally capture the global features of the image. This paper proposes Krawtchouk moment for feature extraction in face recognition system, which has the ability to extract local features from any region of interest. Krawtchouk moment is used to extract both local features and global features of the face. The extracted features are fused using summed normalized distance strategy. Nearest neighbour classifier is employed to classify the faces. The proposed method is tested using ORL and Yale databases. Experimental results show that the proposed method is able to recognize images correctly, even if the images are corrupted with noise and possess change in facial expression and tilt.

  3. Face and Emotion Recognition in MCDD versus PDD-NOS

    Science.gov (United States)

    Herba, Catherine M.; de Bruin, Esther; Althaus, Monika; Verheij, Fop; Ferdinand, Robert F.

    2008-01-01

    Previous studies indicate that Multiple Complex Developmental Disorder (MCDD) children differ from PDD-NOS and autistic children on a symptom level and on psychophysiological functioning. Children with MCDD (n = 21) and PDD-NOS (n = 62) were compared on two facets of social-cognitive functioning: identification of neutral faces and facial…

  4. Unified Model in Identity Subspace for Face Recognition

    Institute of Scientific and Technical Information of China (English)

    Pin Liao; Li Shen; Yi-Qiang Chen; Shu-Chang Liu

    2004-01-01

    Human faces have two important characteristics: (1) They are similar objects and the specific variations of each face are similar to each other; (2) They are nearly bilateral symmetric. Exploiting the two important properties, we build a unified model in identity subspace (UMIS) as a novel technique for face recognition from only one example image per person. An identity subspace spanned by bilateral symmetric bases, which compactly encodes identity information, is presented. The unified model, trained on an obtained training set with multiple samples per class from a known people group A, can be generalized well to facial images of unknown individuals,and can be used to recognize facial images from an unknown people group B with only one sample per subject.Extensive experimental results on two public databases (the Yale database and the Bern database) and our own database (the ICT-JDL database) demonstrate that the UMIS approach is significantly effective and robust for face recognition.

  5. Local Relation Map: A Novel Illumination Invariant Face Recognition Approach

    Directory of Open Access Journals (Sweden)

    Lian Zhichao

    2012-10-01

    Full Text Available In this paper, a novel illumination invariant face recognition approach is proposed. Different from most existing methods, an additive term as noise is considered in the face model under varying illuminations in addition to a multiplicative illumination term. High frequency coefficients of Discrete Cosine Transform (DCT are discarded to eliminate the effect caused by noise. Based on the local characteristics of the human face, a simple but effective illumination invariant feature local relation map is proposed. Experimental results on the Yale B, Extended Yale B and CMU PIE demonstrate the outperformance and lower computational burden of the proposed method compared to other existing methods. The results also demonstrate the validity of the proposed face model and the assumption on noise.

  6. 3D Face Apperance Model

    DEFF Research Database (Denmark)

    Lading, Brian; Larsen, Rasmus; Astrom, K

    2006-01-01

    We build a 3D face shape model, including inter- and intra-shape variations, derive the analytical Jacobian of its resulting 2D rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations......We build a 3D face shape model, including inter- and intra-shape variations, derive the analytical Jacobian of its resulting 2D rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations...

  7. 3D Face Appearance Model

    DEFF Research Database (Denmark)

    Lading, Brian; Larsen, Rasmus; Åström, Kalle

    2006-01-01

    We build a 3d face shape model, including inter- and intra-shape variations, derive the analytical jacobian of its resulting 2d rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations.}......We build a 3d face shape model, including inter- and intra-shape variations, derive the analytical jacobian of its resulting 2d rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations.}...

  8. Carbon-Type Analysis and Comparison of Original and Reblended FACE Diesel Fuels (FACE 2, FACE 4, and FACE 7)

    Energy Technology Data Exchange (ETDEWEB)

    Bays, J. Timothy; King, David L.; O' Hagan, Molly J.

    2012-10-01

    This report summarizes the carbon-type analysis from 1H and 13C{1H} nuclear magnetic resonance spectroscopy (NMR) of Fuels for Advanced Combustion Engines (FACE) diesel blends, FD-2B, FD 4B, and FD-7B, and makes comparison of the new blends with the original FACE diesel blends, FD 2A, FD 4A, and FD-7A, respectively. Generally, FD-2A and FD-2B are more similar than the A and B blends of FD-4 and FD-7. The aromatic carbon content is roughly equivalent, although the new FACE blends have decreased monoaromatic content and increased di- and tri-cycloaromatic content, as well as a higher overall aromatic content, than the original FACE blends. The aromatic components of the new FACE blends generally have a higher alkyl substitution with longer alkyl substituents. The naphthenic and paraffinic contents remained relatively consistent. Based on aliphatic methyl and methylene carbon ratios, cetane numbers for FD-2A and -2B, and FD-7A and -7B are predicted to be consistent, while the cetane number for FD-4B is predicted to be higher than FD-4A. Overall, the new FACE fuel blends are fairly consistent with the original FACE fuel blends, but there are observable differences. In addition to providing important comparative compositional information on reformulated FACE diesel blends, this report also provides important information about the capabilities of the team at Pacific Northwest National Laboratory in the use of NMR spectroscopy for the detailed characterization and comparison of fuels and fuel blends.

  9. Cooperative Path Planning and Constraints Analysis for Master-Slave Industrial Robots

    Directory of Open Access Journals (Sweden)

    Yahui Gan

    2012-09-01

    Full Text Available A strategy of cooperative path planning for a master-slave multiple robot system is presented in this paper. The path planning method is based on motion constraints between the end-effectors of cooperative robots. Cooperation motions have been classified into three types by relative motions between end-effectors of master and slave robots, which is concurrent cooperation, coupled synchronous cooperation and combined synchronous cooperation. Based on this classification, position /orientation constraints and joint velocity constraints are explored in-depth here. In order to validate the path planning method and the theoretical developments in motion constraints analysis, representative experiments based on two industrial robots, Motoman VA1400 and HP20, are provided at the end of the paper. The experimental results have proved both the effectiveness of the path planning method and the correctness of the constraints analysis.

  10. Statistical Model-Based Face Pose Estimation

    Institute of Scientific and Technical Information of China (English)

    GE Xinliang; YANG Jie; LI Feng; WANG Huahua

    2007-01-01

    A robust face pose estimation approach is proposed by using face shape statistical model approach and pose parameters are represented by trigonometric functions. The face shape statistical model is firstly built by analyzing the face shapes from different people under varying poses. The shape alignment is vital in the process of building the statistical model. Then, six trigonometric functions are employed to represent the face pose parameters. Lastly, the mapping function is constructed between face image and face pose by linearly relating different parameters. The proposed approach is able to estimate different face poses using a few face training samples. Experimental results are provided to demonstrate its efficiency and accuracy.

  11. Sensory competition in the face processing areas of the human brain.

    Directory of Open Access Journals (Sweden)

    Krisztina Nagy

    Full Text Available The concurrent presentation of multiple stimuli in the visual field may trigger mutually suppressive interactions throughout the ventral visual stream. While several studies have been performed on sensory competition effects among non-face stimuli relatively little is known about the interactions in the human brain for multiple face stimuli. In the present study we analyzed the neuronal basis of sensory competition in an event-related functional magnetic resonance imaging (fMRI study using multiple face stimuli. We varied the ratio of faces and phase-noise images within a composite display with a constant number of peripheral stimuli, thereby manipulating the competitive interactions between faces. For contralaterally presented stimuli we observed strong competition effects in the fusiform face area (FFA bilaterally and in the right lateral occipital area (LOC, but not in the occipital face area (OFA, suggesting their different roles in sensory competition. When we increased the spatial distance among pairs of faces the magnitude of suppressive interactions was reduced in the FFA. Surprisingly, the magnitude of competition depended on the visual hemifield of the stimuli: ipsilateral stimulation reduced the competition effects somewhat in the right LOC while it increased them in the left LOC. This suggests a left hemifield dominance of sensory competition. Our results support the sensory competition theory in the processing of multiple faces and suggests that sensory competition occurs in several cortical areas in both cerebral hemispheres.

  12. Cross-correlation in face discrimination

    NARCIS (Netherlands)

    Simpson, William A.; Loffler, Gunter; Tucha, Lara

    2013-01-01

    An extensive body of literature suggests that face perception depends critically upon specialised face processing mechanisms. Although it seems clear that specialised face processing is required to explain face recognition, face discrimination is a simpler task that could possibly be solved with a g

  13. Face Recognition Using Double Sparse Local Fisher Discriminant Analysis

    Directory of Open Access Journals (Sweden)

    Zhan Wang

    2015-01-01

    Full Text Available Local Fisher discriminant analysis (LFDA was proposed for dealing with the multimodal problem. It not only combines the idea of locality preserving projections (LPP for preserving the local structure of the high-dimensional data but also combines the idea of Fisher discriminant analysis (FDA for obtaining the discriminant power. However, LFDA also suffers from the undersampled problem as well as many dimensionality reduction methods. Meanwhile, the projection matrix is not sparse. In this paper, we propose double sparse local Fisher discriminant analysis (DSLFDA for face recognition. The proposed method firstly constructs a sparse and data-adaptive graph with nonnegative constraint. Then, DSLFDA reformulates the objective function as a regression-type optimization problem. The undersampled problem is avoided naturally and the sparse solution can be obtained by adding the regression-type problem to a l1 penalty. Experiments on Yale, ORL, and CMU PIE face databases are implemented to demonstrate the effectiveness of the proposed method.

  14. Constraint Specialisation in Horn Clause Verification

    DEFF Research Database (Denmark)

    Kafle, Bishoksan; Gallagher, John Patrick

    2015-01-01

    We present a method for specialising the constraints in constrained Horn clauses with respect to a goal. We use abstract interpretation to compute a model of a query-answer transformation of a given set of clauses and a goal. The effect is to propagate the constraints from the goal top......-down and propagate answer constraints bottom-up. Our approach does not unfold the clauses at all; we use the constraints from the model to compute a specialised version of each clause in the program. The approach is independent of the abstract domain and the constraints theory underlying the clauses. Experimental...

  15. Minimal Model Semantics for Sorted Constraint Representation

    Institute of Scientific and Technical Information of China (English)

    廖乐健; 史忠植

    1995-01-01

    Sorted constraint representation is a very useful representation in AI which combines class hierarchies and constraint networks.For such sorted constraint representation,a problem is how to generalize the idea of default inheritance to constraint network,where the attributes in a class or between different classes interact with each other via the network.To give a formal account for the defeasible reasoning in such representation,a general sorted constraint logic is proposed,and a minimal-model semantics for the logic is presented.

  16. Air Traffic Control in Face of Users’ Demand and Economy Constraints.

    Science.gov (United States)

    1983-02-01

    available "tomorrow" but in reality rapid implementation is restricted by finance and resources. 3.4.2 Avionics/Ground Aids Standards The progressive...op~ration difficile parce qu’elle dolt Stre entreprise A un moment aDl Los instructions relatives A la pr~sentation du projot do budget no mont pan...du budget approuvG ye servir A financer 1 ’achat d’ equip me nts nouf. falwant 1 ’objot dlun aentrat qul pr~voit *ntre autre dons qulle Monnale los

  17. Multiparameter Elastic Full Waveform Inversion With Facies Constraints

    KAUST Repository

    Zhang, Zhendong

    2017-08-17

    Full waveform inversion (FWI) aims fully benefit from all the data characteristics to estimate the parameters describing the assumed physics of the subsurface. However, current efforts to utilize full waveform inversion as a tool beyond acoustic imaging applications, for example in reservoir analysis, faces inherent challenges related to the limited resolution and the potential trade-off between the elastic model parameters. Adding rock physics constraints does help to mitigate these issues, but current approaches to add such constraints are based on including them as a priori knowledge mostly valid around the well or as a boundary condition for the whole area. Since certain rock formations inside the Earth admit consistent elastic properties and relative values of elastic and anisotropic parameters (facies), utilizing such localized facies information in FWI can improve the resolution of inverted parameters. We propose a novel confidence map based approach to utilize the facies-based constraints in both isotropic and anisotropic elastic FWI. We invert for such a confidence map using Bayesian theory, in which the confidence map is updated at each iteration of the inversion using both the inverted models and a prior information. The numerical examples show that the proposed method can reduce the trade-offs and also can improve the resolution of the inverted elastic and anisotropic properties.

  18. Weighted Constraint Satisfaction for Smart Home Automation and Optimization

    Directory of Open Access Journals (Sweden)

    Noel Nuo Wi Tay

    2016-01-01

    Full Text Available Automation of the smart home binds together services of hardware and software to provide support for its human inhabitants. The rise of web technologies offers applicable concepts and technologies for service composition that can be exploited for automated planning of the smart home, which can be further enhanced by implementation based on service oriented architecture (SOA. SOA supports loose coupling and late binding of devices, enabling a more declarative approach in defining services and simplifying home configurations. One such declarative approach is to represent and solve automated planning through constraint satisfaction problem (CSP, which has the advantage of handling larger domains of home states. But CSP uses hard constraints and thus cannot perform optimization and handle contradictory goals and partial goal fulfillment, which are practical issues smart environments will face if humans are involved. This paper extends this approach to Weighted Constraint Satisfaction Problem (WCSP. Branch and bound depth first search is used, where its lower bound is estimated by bacterial memetic algorithm (BMA on a relaxed version of the original optimization problem. Experiments up to 16-step planning of home services demonstrate the applicability and practicality of the approach, with the inclusion of local search for trivial service combinations in BMA that produces performance enhancements. Besides, this work aims to set the groundwork for further research in the field.

  19. Préface

    Science.gov (United States)

    Ouerdane, Youcef; Laporte, Pierre

    2005-06-01

    égime UVX ultra-bref (CELIA)... Dans le domaine que l'on peut appeler, au sens large, “travail des matériaux”, on distinguera particulièrement les avancées dans le domaine de la microlithographie “prévues” par road map, avec l'arrivée semble-t-il inéluctable des technologies UVX à 13,5 nm. Les enjeux économiques favorisent des avancées technologiques multiples (optiques multicouches en réflexion, sources...). Par ailleurs l'aptitude des technologies femto pour l'ablation quasi athermique (micro-usinage) et le dépôt de couches minces spécifiques se confirme tout à fait. Enfin, à fluence plus faible, l'outil laser reste un instrument de choix pour l'étude de l'interaction photon-surface : désorption sous illumination laser à excimères à 157 nm et photoémission/photoconductivité du diamant sous éclairement ultra-bref de l'infrarouge à l'UVX. Nous tenons à remercier les membres du comité d'organisation, le comité scientifique et les différents partenaires, institutionnels et industriels, qui par leur soutien ont permis que le colloque UVX puisse se dérouler. Ce colloque a été parrainé par plusieurs départements du CNRS, la Délégation Générale de l'Armement (DGA), le CEA DRECAM, le CEA DAM, le Conseil Général de la Loire, l'Université Jean MONNET de Saint-Étienne, Saint-Étienne Métropole, la ville de Saint-Étienne, Le Pôle Optique Rhône-Alpes, la Société Française d'Optique et le Groupement de Recherche “SAXO” du CNRS. À tous, nous donnons rendez-vous à Caen pour UVX-2006. Youcef OUERDANE Pierre LAPORTE

  20. A Maximal Tractable Class of Soft Constraints

    CERN Document Server

    Cohen, D; Jeavons, P; Krokhin, A; 10.1613/jair.1400

    2011-01-01

    Many researchers in artificial intelligence are beginning to explore the use of soft constraints to express a set of (possibly conflicting) problem requirements. A soft constraint is a function defined on a collection of variables which associates some measure of desirability with each possible combination of values for those variables. However, the crucial question of the computational complexity of finding the optimal solution to a collection of soft constraints has so far received very little attention. In this paper we identify a class of soft binary constraints for which the problem of finding the optimal solution is tractable. In other words, we show that for any given set of such constraints, there exists a polynomial time algorithm to determine the assignment having the best overall combined measure of desirability. This tractable class includes many commonly-occurring soft constraints, such as 'as near as possible' or 'as soon as possible after', as well as crisp constraints such as 'greater than'. F...