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Intuitive
Terms modified by Intuitive Selected AbstractsRobotic single-port transumbilical surgery in humans: initial reportBJU INTERNATIONAL, Issue 3 2009Jihad H. Kaouk OBJECTIVE To describe our initial clinical experience of robotic single-port (RSP) surgery. PATIENTS AND METHODS The da Vinci® S robot (Intuitive, Sunnyvale, CA, USA) was used to perform radical prostatectomy (RP), dismembered pyeloplasty, and radical nephrectomy. A robot 12-mm scope and 5-mm robotic grasper were introduced through a multichannel single port (R-port, Advanced Surgical Concepts, Dublin, Ireland). An additional 5-mm or 8-mm robotic port was introduced through the same umbilical incision (2 cm) alongside the multichannel port and used to introduce robotic instruments. Vesico-urethral anastomosis and pelvi-ureteric anastomosis were successfully performed robotically using running intracorporeal suturing. RESULTS All three RSP surgeries were performed through the single incision without adding extra umbilical ports or 2-mm instruments. For RP, the operative duration was 5 h and the estimated blood loss was 250 mL. The hospital stay was 36 h and the margins of resection were negative. For pyeloplasty, the operative duration was 4.5 h, and the hospital stay was 50 h. Right radical nephrectomy for a 5.5-cm renal cell carcinoma was performed in 2.5 h and the hospital stay was 48 h. The specimen was extracted intact within an entrapment bag through the umbilical incision. There were no intraoperative or postoperative complications. At 1 week after surgery, all patients had minimal pain with a visual analogue score of 0/10. CONCLUSIONS Technical challenges of single-port surgery that may limit its widespread acceptance can be addressed by using robotic technology. Articulation of robotic instruments may render obsolete the long-held laparoscopic principles of triangulation especially for intracorporeal suturing. We report the initial series of robotic surgery through a single transumbilical incision. [source] Inhomogeneous volumetric Laplacian deformation for rhinoplasty planning and simulation systemCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2010Sheng-hui Liao Abstract This paper presents an intuitive rhinoplasty planning and simulation system, to provide high quality prediction of postoperative appearance, and design patient specific nose prosthesis automatically. The key component is a novel volumetric Laplacian deformation tool inspired by the state-of-the-art differential surface deformation techniques. Working on the volumetric domain and incorporating inhomogeneous material from CT data make the new approach suitable for soft tissue simulation. In particular, the system employs a special sketch contour driving deformation interface, which can provide realistic 3D rhinoplasty simulation with intuitive and straightforward 2D manipulation. When satisfied with the appearance, the change of soft tissue before and after simulation is utilized to generate the individual prosthesis model automatically. Clinical validation using post-operative CT data demonstrated that the system can provide prediction results of high quality. And the surgeons who used the system confirmed that this planning system is attractive and has potential for daily clinical practice. Copyright © 2010 John Wiley & Sons, Ltd. [source] Furstyling on angle-split shell texturesCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 2-3 2009Bin Sheng Abstract This paper presents a new method for modeling and rendering fur with a wide variety of furstyles. We simulate virtual fur using shell textures,a multiple layers of textured slices for its generality and efficiency. As shell textures usually suffer from the inherent visual gap errors due to the uniform discretization nature, we present the angle-split shell textures (ASST) approach, which classifies the shell textures into different types with different numbers of texture layers, by splitting the angle space of the viewing angles between fur orientation and view direction. Our system can render the fur with biological patterns, and utilizes vector field and scalar field on ASST to control the geometric variations of the furry shape. Users can intuitively shape the fur by applying the combing, blowing, and interpolating effects in real time. Our approach is intuitive to implement without using complex data structures, with real-time performance for dynamic fur appearances. Copyright © 2009 John Wiley & Sons, Ltd. [source] Interactive shadowing for 2D AnimeCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 2-3 2009Eiji Sugisaki Abstract In this paper, we propose an instant shadow generation technique for 2D animation, especially Japanese Anime. In traditional 2D Anime production, the entire animation including shadows is drawn by hand so that it takes long time to complete. Shadows play an important role in the creation of symbolic visual effects. However shadows are not always drawn due to time constraints and lack of animators especially when the production schedule is tight. To solve this problem, we develop an easy shadowing approach that enables animators to easily create a layer of shadow and its animation based on the character's shapes. Our approach is both instant and intuitive. The only inputs required are character or object shapes in input animation sequence with alpha value generally used in the Anime production pipeline. First, shadows are automatically rendered on a virtual plane by using a Shadow Map1 based on these inputs. Then the rendered shadows can be edited by simple operations and simplified by the Gaussian Filter. Several special effects such as blurring can be applied to the rendered shadow at the same time. Compared to existing approaches, ours is more efficient and effective to handle automatic shadowing in real-time. Copyright © 2009 John Wiley & Sons, Ltd. [source] Real-time cartoon animation of smokeCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2005Haitao He Abstract In this paper, we present a practical framework to generate cartoon style animations of smoke, which consists of two components: a smoke simulator and a rendering system. In the simulation stage, the smoke is modelled as a set of smoothed particles and the physical parameters such as velocity and force are defined on particles directly. The smoke is rendered in flicker-free cartoon style with two-tone shading and silhouettes. Both the simulation and rendering are intuitive and easy to implement. In the most moderate scale scene, an impressive cartoon animation is generated with about a thousand particles at real-time frame rate. Copyright © 2005 John Wiley & Sons, Ltd. [source] TouchTone: Interactive Local Image Adjustment Using Point-and-SwipeCOMPUTER GRAPHICS FORUM, Issue 2 2010Chia-Kai Liang Recent proliferation of camera phones, photo sharing and social network services has significantly changed how we process our photos. Instead of going through the traditional download-edit-share cycle using desktop editors, an increasing number of photos are taken with camera phones and published through cellular networks. The immediacy of the sharing process means that on-device image editing, if needed, should be quick and intuitive. However, due to the limited computational resources and vastly different user interaction model on small screens, most traditional local selection methods can not be directly adapted to mobile devices. To address this issue, we present TouchTone, a new method for edge-aware image adjustment using simple finger gestures. Our method enables users to select regions within the image and adjust their corresponding photographic attributes simultaneously through a simple point-and-swipe interaction. To enable fast interaction, we develop a memory- and computation-efficient algorithm which samples a collection of 1D paths from the image, computes the adjustment solution along these paths, and interpolates the solutions to entire image through bilateral filtering. Our system is intuitive to use, and can support several local editing tasks, such as brightness, contrast, and color balance adjustments, within a minute on a mobile device. [source] BetweenIT: An Interactive Tool for Tight InbetweeningCOMPUTER GRAPHICS FORUM, Issue 2 2010Brian Whited Abstract The generation of inbetween frames that interpolate a given set of key frames is a major component in the production of a 2D feature animation. Our objective is to considerably reduce the cost of the inbetweening phase by offering an intuitive and effective interactive environment that automates inbetweening when possible while allowing the artist to guide, complement, or override the results. Tight inbetweens, which interpolate similar key frames, are particularly time-consuming and tedious to draw. Therefore, we focus on automating these high-precision and expensive portions of the process. We have designed a set of user-guided semi-automatic techniques that fit well with current practice and minimize the number of required artist-gestures. We present a novel technique for stroke interpolation from only two keys which combines a stroke motion constructed from logarithmic spiral vertex trajectories with a stroke deformation based on curvature averaging and twisting warps. We discuss our system in the context of a feature animation production environment and evaluate our approach with real production data. [source] Lighting and Occlusion in a Wave-Based FrameworkCOMPUTER GRAPHICS FORUM, Issue 2 2008Remo Ziegler Abstract We present novel methods to enhance Computer Generated Holography (CGH) by introducing a complex-valued wave-based occlusion handling method. This offers a very intuitive and efficient interface to introduce optical elements featuring physically-based light interaction exhibiting depth-of-field, diffraction, and glare effects. Fur-thermore, an efficient and flexible evaluation of lit objects on a full-parallax hologram leads to more convincing images. Previous illumination methods for CGH are not able to change the illumination settings of rendered holo-grams. In this paper we propose a novel method for real-time lighting of rendered holograms in order to change the appearance of a previously captured holographic scene. These functionalities are features of a bigger wave-based rendering framework which can be combined with 2D framebuffer graphics. We present an algorithm which uses graphics hardware to accelerate the rendering. [source] Dye Advection Without the Blur: A Level-Set Approach for Texture-Based Visualization of Unsteady FlowCOMPUTER GRAPHICS FORUM, Issue 3 2004D. Weiskopf Dye advection is an intuitive and versatile technique to visualize both steady and unsteady flow. Dye can be easily combined with noise-based dense vector field representations and is an important element in user-centric visual exploration processes. However, fast texture-based implementations of dye advection rely on linear interpolation operations that lead to severe diffusion artifacts. In this paper, a novel approach for dye advection is proposed to avoid this blurring and to achieve long and clearly defined streaklines or extended streak-like patterns. The interface between dye and background is modeled as a level-set within a signed distance field. The level-set evolution is governed by the underlying flow field and is computed by a semi-Lagrangian method. A reinitialization technique is used to counteract the distortions introduced by the level-set evolution and to maintain a level-set function that represents a local distance field. This approach works for 2D and 3D flow fields alike. It is demonstrated how the texture-based level-set representation lends itself to an efficient GPU implementation and therefore facilitates interactive visualization. Categories and Subject Descriptors (according to ACM CCS): I.3.3 [Computer Graphics]: Picture/Image Generation I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism [source] "Visible Signs of a City Out of Control": Community Policing in New York CityCULTURAL ANTHROPOLOGY, Issue 2 2004Benjamin Chesluk ABSTRACT Institutions of police,community dialogue in New York City assume that communities possess an intuitive and legally sound sense of order and disorder, on which the police can rely for information and support. However, staged dialogues between police and community groups can produce complicated situations of conflict and tension. While the police work to interpellate a friendly, coherent, and controlled community subject, city residents use the police's ideological language of order to offer a critique of the police themselves and of the sweeping neoliberal economic restructuring of the city around them. [source] Species prioritization for monitoring and management in regional multiple species conservation plansDIVERSITY AND DISTRIBUTIONS, Issue 3 2008Helen M. Regan ABSTRACT Successful conservation plans are not solely achieved by acquiring optimally designed reserves. Ongoing monitoring and management of the biodiversity in those reserves is an equally important, but often neglected or poorly executed, part of the conservation process. In this paper we address one of the first and most important steps in designing a monitoring program , deciding what to monitor. We present a strategy for prioritizing species for monitoring and management in multispecies conservation plans. We use existing assessments of threatened status, and the degree and spatial and temporal extent of known threats to link the prioritization of species to the overarching goals and objectives of the conservation plan. We consider both broad and localized spatial scales to capture the regional conservation context and the practicalities of local management and monitoring constraints. Spatial scales that are commensurate with available data are selected. We demonstrate the utility of this strategy through application to a set of 85 plants and animals in an established multispecies conservation plan in San Diego County, California, USA. We use the prioritization to identify the most prominent risk factors and the habitats associated with the most threats to species. The protocol highlighted priorities that had not previously been identified and were not necessarily intuitive without systematic application of the criteria; many high-priority species have received no monitoring attention to date, and lower-priority species have. We recommend that in the absence of clear focal species, monitoring threats in highly impacted habitats may be a way to circumvent the need to monitor all the targeted species. [source] Ecological boundary detection using Carlin,Chib Bayesian model selectionDIVERSITY AND DISTRIBUTIONS, Issue 6 2005Ralph Mac Nally ABSTRACT Sharp ecological transitions in space (ecotones, edges, boundaries) often are where ecologically important events occur, such as elevated or reduced biodiversity or altered ecological functions (e.g. changes in productivity, pollination rates or parasitism loads, nesting success). While human observers often identify these transitions by using intuitive or gestalt assignments (e.g. the boundary between a remnant woodland patch and the surrounding farm paddock seems obvious), it is clearly desirable to make statistical assessments based on measurements. These assessments often are straightforward to make if the data are univariate, but identifying boundaries or transitions using compositional or multivariate data sets is more difficult. There is a need for an intermediate step in which pairwise similarities between points or temporal samples are computed. Here, I describe an approach that treats points along a transect as alternative hypotheses (models) about the location of the boundary. Carlin and Chib (1995) introduced a Bayesian technique for comparing non-hierarchical models, which I adapted to compute the probabilities of each boundary location (i.e. a model) relative to the ensemble of models constituting the set of possible points of the boundary along the transect. Several artificial data sets and two field data sets (on vegetation and soils and on cave-dwelling invertebrates and microclimates) are used to illustrate the approach. The method can be extended to cases in with several boundaries along a gradient, such as where there is an ecotone of non-zero thickness. [source] A minimum sample size required from Schmidt hammer measurementsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2009Tomasz Niedzielski Abstract The Schmidt hammer is a useful tool applied by geomorphologists to measure rock strength in field conditions. The essence of field application is to obtain a sufficiently large dataset of individual rebound values, which yields a meaningful numerical value of mean strength. Although there is general agreement that a certain minimum sample size is required to proceed with the statistics, the choice of size (i.e. number of individual impacts) was usually intuitive and arbitrary. In this paper we show a simple statistical method, based on the two-sample Student's t -test, to objectively estimate the minimum number of rebound measurements. We present the results as (1) the ,mean' and ,median' solutions, each providing a single estimate value, and (2) the empirical probability distribution of such estimates based on many field samples. Schmidt hammer data for 14 lithologies, 13,81 samples for each, with each sample consisting of 40 individual readings, have been evaluated, assuming different significance levels. The principal recommendations are: (1) the recommended minimum sample size for weak and moderately strong rock is 25; (2) a sample size of 15 is sufficient for sandstones and shales; (3) strong and coarse rocks require 30 readings at a site; (4) the minimum sample size may be reduced by one-third if the context of research allows for higher significance level for test statistics. Interpretations based on less than 10 readings from a site should definitely be avoided. Copyright © 2009 John Wiley & Sons, Ltd. [source] Cover Picture: Electrophoresis 7'09ELECTROPHORESIS, Issue 7 2009Article first published online: 16 APR 200 Issue no. 7 is a special issue on "Biomarker Discovery and Related Topics". It has 18 articles distributed among four parts including genomic, proteomic, glycoproteomic and metabolomic markers. "New separation technologies, improvements of existing methods and intuitive, elegant applications are providing a representative snapshot on the "state-of-the-art" of the bioanalytical aspects of biomarker discovery today". In addition, as recognition of his significant contribution to the field, this special issue is dedicated to the 70th birthday of Professor Barry L. Karger. [source] Untangling the Intuition Mess: Intuition as a Construct in Entrepreneurship ResearchENTREPRENEURSHIP THEORY AND PRACTICE, Issue 6 2005J. Robert Mitchell Entrepreneurs often use intuition to explain their actions. But because entrepreneurial intuition is poorly defined in the research literature: the "intuitive" is confused with the "innate," what is systematic is overlooked, and unexplained variance in entrepreneurial behavior remains high. Herein we: (1) bound and define the construct of entrepreneurial intuition within the distinctive domain of entrepreneurship research; (2) apply a levels-of-consciousness logic and process dynamism approach to; (3) organize definitions, antecedents, and consequences; and (4) produce propositions that lead to a working definition of entrepreneurial intuition. Our analysis renders intuition more usable in entrepreneurship research, and more valuable in practice. [source] On the use of generalized linear models for interpreting climate variabilityENVIRONMETRICS, Issue 7 2005Richard E. Chandler Abstract Many topical questions in climate research can be reduced to either of two related problems: understanding how various different components of the climate system affect each other, and quantifying changes in the system. This article aims to justify the addition of generalized linear models to the climatologist's toolkit, by demonstrating that they offer an intuitive and flexible approach to such problems. In particular, we provide some suggestions as to how ,typical' climatological data structures may be represented within the GLM framework. Recurring themes include methods for space,time data and the need to cope with large datasets. The ideas are illustrated using a dataset of monthly U.S. temperatures. Copyright © 2005 John Wiley & Sons, Ltd. [source] Spinoza on the Problem of AkrasiaEUROPEAN JOURNAL OF PHILOSOPHY, Issue 1 2010Eugene Marshall Though each is intuitive in a certain way, they both fail as explanations of the most interesting cases of akrasia. Spinoza's own thoughts on bondage and the affects follow, from which a Spinozist explanation of akrasia is constructed. This account is based in Spinoza's mechanistic psychology of cognitive affects. Because Spinoza's account explains action asissuing from modes of mind that are both cognitive and affective, it captures the intuitions that motivate the two traditional views while avoiding the pitfalls that result from their one-sided approaches. This project will allow us a fuller understanding of Spinozist moral psychology. In addition to this historical value, the Spinozist theory may offer a satisfactory explanation of certain hard cases of akrasia while avoiding the problems be set by other theories. For this reason, the Spinozist account could also be seen as a useful contribution to our philosophical understanding of the phenomenon of akrasia. [source] Nonverbal Communication: How To Read What's Plain as the Nose, or Eyelid, or Chin, on Their FacesGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 2 2001Mac Fulfer For most people, "reading" others' nonverbal messages is an intuitive, "gut" process. But learning to do it consciously and deliberately can enhance understanding and thus greatly improve interpersonal relations in a wide variety of situations. At work, it can be a useful tool to facilitate decision making and ease work processes,for example, during interviews or at meetings. © 2001 John Wiley & Sons, Inc. [source] Towards an integrated computational tool for spatial analysis in macroecology and biogeographyGLOBAL ECOLOGY, Issue 4 2006Thiago Fernando L. V. B. Rangel ABSTRACT Because most macroecological and biodiversity data are spatially autocorrelated, special tools for describing spatial structures and dealing with hypothesis testing are usually required. Unfortunately, most of these methods have not been available in a single statistical package. Consequently, using these tools is still a challenge for most ecologists and biogeographers. In this paper, we present sam (Spatial Analysis in Macroecology), a new, easy-to-use, freeware package for spatial analysis in macroecology and biogeography. Through an intuitive, fully graphical interface, this package allows the user to describe spatial patterns in variables and provides an explicit spatial framework for standard techniques of regression and correlation. Moran's I autocorrelation coefficient can be calculated based on a range of matrices describing spatial relationships, for original variables as well as for residuals of regression models, which can also include filtering components (obtained by standard trend surface analysis or by principal coordinates of neighbour matrices). sam also offers tools for correcting the number of degrees of freedom when calculating the significance of correlation coefficients. Explicit spatial modelling using several forms of autoregression and generalized least-squares models are also available. We believe this new tool will provide researchers with the basic statistical tools to resolve autocorrelation problems and, simultaneously, to explore spatial components in macroecological and biogeographical data. Although the program was designed primarily for the applications in macroecology and biogeography, most of sam's statistical tools will be useful for all kinds of surface pattern spatial analysis. The program is freely available at http://www.ecoevol.ufg.br/sam (permanent URL at http://purl.oclc.org/sam/). [source] A resource-based conceptual model of plant diversity that reassesses causality in the productivity,diversity relationshipGLOBAL ECOLOGY, Issue 3 2006Chris Lavers ABSTRACT Biogeographical studies frequently reveal positive correlations between species richness and estimates of environmental water and/or energy. A popular interpretation of this relationship relates the supply of water and energy to productivity, and then, in turn, to richness. Productivity,diversity theories are now legion, yet none has proved sufficiently intuitive to gain broad acceptance. Like productivity, heterogeneity is known to influence diversity at fine spatial scales, yet the possibility that richness might relate to water,energy dynamics at coarse spatial scales via a heterogeneity-generating mechanism has received little attention. In this paper we outline such a conceptual model for plants that is internally consistent and testable. We believe it may help to explain the capacity of environments receiving different inputs of water and energy to support variable numbers of species at a range of spatial scales, the pervasive correlation between productivity and richness, some exceptions to the productivity,diversity relationship, the form of productivity,diversity curves and the link between richness and environmental ,harshness'. The model may also provide an answer to one of the most venerable puzzles in the field of diversity studies: why high inputs of water and energy correspond to more species rather than simply more individuals. [source] Idiopathic Intracranial Hypertension and PostlumbarPuncture HeadacheHEADACHE, Issue 2 2004Yince Loh MD Idiopathic intracranial hypertension and low cerebrospinal pressure are 2 conditions that are thought to be on opposite ends of the cerebrospinal pressure spectrum. Headache is the prominent component of both conditions. We describe a patient whose evaluation for idiopathic intracranial hypertension resulted in a postlumbar puncture headache. Although not entirely intuitive, we suggest that the 2 conditions can be present in the same patient. [source] Malnutrition, poverty, and economic growthHEALTH ECONOMICS, Issue S1 2009Rasmus Heltberg Abstract This paper argues that indicators of anthropometric shortfall , especially low height and low weight-for-age , are uniquely suited for assessing absolute deprivation in developing countries. Anthropometric indicators are relatively precise, readily available for most countries, reflect the preferences and concerns of many poor people, consistent with reckoning the phenomenon directly in the space of functionings, intuitive, easy to use for advocacy, and consistent over time and across subgroups. Anthropometric indicators can therefore complement (but not replace) standard indicators of income/consumption poverty, especially for comparisons across subgroups, within households, across countries, and in the long run. In addition, the paper analyses spells of change in malnutrition over time, finding that the association between economic growth and chronic child malnutrition is very small (but statistically significant) and much lower than the elasticity of growth on poverty. The policy implication of this finding is that direct interventions aimed at reducing infant malnutrition are required. Copyright © 2009 John Wiley & Sons, Ltd. [source] Analytical study of mine closure behaviour in a poro-visco-elastic mediumINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 14 2008H. Wong Abstract This paper is interested in the hydro-mechanical behaviour of an underground cavity abandoned at the end of its service life. It is an extension of a previous study that accounted for a poro-elastic behaviour of the rock mass (Int. J. Comput. Geomech. 2007; DOI: 10.1016/j.compgeo.2007.11.003). Deterioration of the lining support with time leads to the transfer of the loading from the exterior massif to the interior backfill. The in situ material has a poro-visco-elastic constitutive behaviour while the backfill is poro-elastic, both saturated with water. This loading transfer is accompanied by an inward cavity convergence, thereby compressing the backfill, and induces an outward water flow. This leads to a complex space,time evolution of pore pressures, displacements and stresses, which is not always intuitive. In its general setting, a semi-explicit solution to this problem is developed, using Laplace transform, the inversion being performed numerically. Analytical inversion leading to a quasi-explicit solution in the time domain is possible by identifying the characteristic creep and relaxation times of volumetric strains with those of the deviatoric strains, on the basis of a parametric study. A few numerical examples are given to illustrate the hydro-mechanical behaviour of the cavity and highlight the influence of key parameters (e.g. stiffness of backfill, lining deterioration rate, etc.). Further studies accounting for more general material behaviours for the backfill and external ground are ongoing. Copyright © 2008 John Wiley & Sons, Ltd. [source] Thermodynamically consistent phase-field models of fracture: Variational principles and multi-field FE implementationsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 10 2010C. Miehe Abstract The computational modeling of failure mechanisms in solids due to fracture based on sharp crack discontinuities suffers in situations with complex crack topologies. This can be overcome by a diffusive crack modeling based on the introduction of a crack phase-field. In this paper, we outline a thermodynamically consistent framework for phase-field models of crack propagation in elastic solids, develop incremental variational principles and consider their numerical implementations by multi-field finite element methods. We start our investigation with an intuitive and descriptive derivation of a regularized crack surface functional that ,-converges for vanishing length-scale parameter to a sharp crack topology functional. This functional provides the basis for the definition of suitable convex dissipation functions that govern the evolution of the crack phase-field. Here, we propose alternative rate-independent and viscous over-force models that ensure the local growth of the phase-field. Next, we define an energy storage function whose positive tensile part degrades with increasing phase-field. With these constitutive functionals at hand, we derive the coupled balances of quasi-static stress equilibrium and gradient-type phase-field evolution in the solid from the argument of virtual power. Here, we consider a canonical two-field setting for rate-independent response and a time-regularized three-field formulation with viscous over-force response. It is then shown that these balances follow as the Euler equations of incremental variational principles that govern the multi-field problems. These principles make the proposed formulation extremely compact and provide a perfect base for the finite element implementation, including features such as the symmetry of the monolithic tangent matrices. We demonstrate the performance of the proposed phase-field formulations of fracture by means of representative numerical examples. Copyright © 2010 John Wiley & Sons, Ltd. [source] Analysis of resequencing in downloadsINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 8 2003Yoav Nebat Abstract Recent studies indicate that out-of-order arrival of data packets during downloads of resources is not pathological network behaviour (ACM/IEEE Trans. Networking 1999; 7(6):789). Though this situation is most intuitive when packets of the same resource arrive in parallel from several sources, it turns out that this phenomenon may also occur in the single source scenario. Knowledge regarding the expected reordering needed is important both for being able to decide on the size of the resequencing buffer needed, and to estimate the burstiness in arrival of data to the application. In this study we present a method to calculate the resequencing buffer occupancy probabilities for the single source scenario, and a study of the resequencing buffer occupancy for the two source scenario, where arrival from each of the sources is in order. Copyright © 2003 John Wiley & Sons, Ltd. [source] Bipolar preference modeling and aggregation in decision supportINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 9 2008Meltem Öztürk The article discusses the use of positive and negative reasons when preferences about alternative options have to be considered. Besides explaining the intuitive and formal situations where such a bipolar reasoning is used, the article shows how it is possible to generalize the concordance/discordance principle in preference aggregation and apply it to the problem of aggregating preferences expressed under intervals. © 2008 Wiley Periodicals, Inc. [source] Wound care in the community setting: clinical decision making in contextJOURNAL OF ADVANCED NURSING, Issue 4 2000Christine E. Hallett PhD BNurs BA Hons RGN HVCert DNCert PGDE Wound care in the community setting: clinical decision making in context Sixty-two community nurses in northern England of grades B and D to H were interviewed by a team of four researchers. The interviews were semi-structured, and were tape-recorded, fully transcribed and content analysed. They were conducted as part of a larger study, the aim of which was to examine community nurses' perceptions of quality in nursing care. One of the main themes the work focused on was decision-making as an element of quality. Data relating to wound care were considered from the perspective of the insights they offered into clinical decision-making. Data were interpreted in the light of a literature review in which a distinction had been made between theories which represented clinical decision-making as a linear or staged process and those which represented it as intuitive. Within the former category, three sub-categories were suggested: theorists could be divided into ,pragmatists', ,systematisers' and those who advocated ,diagnostic reasoning'. The interpretation of the data suggested that the clinical decisions made by community nurses in the area of wound care appeared largely intuitive, yet were also closely related to ,diagnostic reasoning'. They were furthermore based on a range of sources of information and justified by a number of different types of rationale. [source] a MATTER of transFORMationJOURNAL OF ARCHITECTURAL EDUCATION, Issue 4 2005ANTHONY VISCARDI Gaston Bachelard contends that two types of imagination inform the creative process: a formal imagination and a material imagination. Formal causes stem from intuitive and associative image production, and lead to a process of conceptualization that provides the analytical tools to create an object. Material imagination is provoked solely and directly from our immediate confrontation and manipulation of matter. These images may be assigned category by the eye but only the hand truly reveals them. [source] Individual strategy preferences and decisional fitJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 5 2008Cornelia Betsch Abstract The present research introduces the concept of decisional fit. A decision maker experiences decisional fit when the individually preferred decision strategy fits the actually applied strategy. In accordance to other fit-concepts in psychology (e.g., person,environment fit), we expected positive effects of decisional fit. Five studies examine the effects of a fit between the individual preference for intuition and deliberation (PID) and the actually used decision strategy (intuition or deliberation). A comparison of extreme types (according to participants' values on the PID scale) revealed that decisional fit enhances the perceived value of the chosen or evaluated object (Studies 1,3). In Studies 4 and 5, participants experienced less regret after decisional fit. The findings highlight the importance of considering individual differences when comparing intuitive and deliberate decision making, because strategy preferences interact with applied strategies. Copyright © 2008 John Wiley & Sons, Ltd. [source] Reduced Fluoroscopy During Atrial Fibrillation Ablation: Benefits of Robotic Guided NavigationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2010DANIEL STEVEN M.D. Reduced Fluoroscopy in PVI Using RN.,Background: Recently, a nonmagnetic robotic navigation system (RN, Hansen-SenseiÔ) has been introduced for remote catheter manipulation. Objective: To investigate the influence of RN combined with intuitive 3-dimensional mapping on the fluoroscopy exposure to operator and patient during pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) in a prospective randomized trial. Methods: Sixty patients were randomly assigned to undergo PVI either using a RN guided (group 1; n = 30, 20 male, 62 ± 7.7 years) or conventional ablation approach (group 2; n = 30, 14 male, 61 ± 7.6 years). A 3-dimensional mapping system (NavXÔ) was used in both groups. Results: Electrical disconnection of the ipsilateral pulmonary veins (PVs) was achieved in all patients. Use of RN significantly lowered the overall fluoroscopy time (9 ± 3.4 vs 22 ± 6.5 minutes; P < 0.001) and reduced the operator's fluoroscopy exposure (7 ± 2.1 vs 22 ± 6.5 minutes; P < 0.001). The difference in fluoroscopy duration between both groups was most pronounced during the ablation part of the procedure (3 ± 2.4 vs 17 ± 6.3 minutes; P < 0.001). The overall procedure duration tended to be prolonged using RN without reaching statistical significance (156 ± 44.4 vs 134 ± 12 minutes, P = 0.099). No difference regarding outcome was found during a midterm follow-up of 6 months (AF freedom group 1 = 73% vs 77% in group 2 [P = 0.345]). Conclusion: The use of RN for PVI seems to be effective and significantly reduces overall fluoroscopy time and operator's fluoroscopy exposure without affecting mid-term outcome after 6-month follow-up. (J Cardiovasc Electrophysiol, Vol. 21, pp. 6,12, January 2010) [source] | |||||||||||||||||||||||||||||||||||||