bluuebunny/crossref_metadata_2025 huggingface dataset:
A layered, heterogeneous reflectance model for acquiring and rendering human skin
Authors: Donner Craig , Weyrich Tim , d'Eon Eugene , Ramamoorthi Ravi , Rusinkiewicz Szymon
Published: December 2008

We introduce a layered, heterogeneous spectral reflectance model for human skin. The model captures the inter-scattering of light among layers, each of which may have an independent set of spatially-varying absorption and scattering parameters. For greater physical accuracy and control, we introduce an infinitesimally thin absorbing layer between scattering layers. To obtain parameters for our model, we use a novel acquisition method that begins with multi-spectral photographs. By using an inverse rendering technique, along with known chromophore spectra, we optimize for the best set of parameters for each pixel of a patch. Our method finds close matches to a wide variety of inputs with low residual error.

We apply our model to faithfully reproduce the complex variations in skin pigmentation. This is in contrast to most previous work, which assumes that skin is homogeneous or composed of homogeneous layers. We demonstrate the accuracy and flexibility of our model by creating complex skin visual effects such as veins, tattoos, rashes, and freckles, which would be difficult to author using only albedo textures at the skin's outer surface. Also, by varying the parameters to our model, we simulate effects from external forces, such as visible changes in blood flow within the skin due to external pressure.
Subdivision shading
Authors: Alexa Marc , Boubekeur Tamy
Published: December 2008

The idea of Phong Shading is applied to subdivision surfaces: normals are associated with vertices and the same construction is used for both locations and normals. This creates vertex positions
and
normals. The vertex normals are smoother than the normals of the subdivision surface and using vertex normals for shading attenuates the well known visual artifacts of many subdivision schemes. We demonstrate how to apply subdivision to normals and how blend and combine different normals for achieving a variety of effects.
Deducing interpolating subdivision schemes from approximating subdivision schemes
Authors: Lin Shujin , You Fang , Luo Xiaonan , Li Zheng
Published: December 2008

In this paper we describe a method for directly deducing new interpolating subdivision masks for meshes from corresponding approximating subdivision masks. The purpose is to avoid complex computation for producing interpolating subdivision masks on extraordinary vertices. The method can be applied to produce new interpolating subdivision schemes, solve some limitations in existing interpolating subdivision schemes and satisfy some application needs. As cases, in this paper a new interpolating subdivision scheme for polygonal meshes is produced by deducing from the Catmull-Clark subdivision scheme. It can directly operate on polygonal meshes, which solves the limitation of Kobbelt's interpolating subdivision scheme. A new √3 interpolating subdivision scheme for triangle meshes and a new √2 interpolating subdivision scheme for quadrilateral meshes are also presented in the paper by deducing from √3 subdivision schemes and 4-8 subdivision schemes respectively. They both produce
C
1
continuous limit surfaces and avoid the blemish in the existing interpolating √3 and √2 subdivision masks where the weight coefficients on extraordinary vertices can not be described by formulation explicitly. In addition, by adding a parameter to control the transition from approximation to interpolation, they can produce surfaces intervening between approximating and interpolating which can be used to solve the "popping effect" problem when switching between meshes at different levels of resolution. They can also force surfaces to interpolate chosen vertices.
Spectral quadrangulation with orientation and alignment control
Authors: Huang Jin , Zhang Muyang , Ma Jin , Liu Xinguo , Kobbelt Leif , Bao Hujun
Published: December 2008

This paper presents a new quadrangulation algorithm, extending the spectral surface quadrangulation approach where the coarse quadrangular structure is derived from the Morse-Smale complex of an eigenfunction of the Laplacian operator on the input mesh. In contrast to the original scheme, we provide flexible explicit controls of the shape, size, orientation and feature alignment of the quadrangular faces. We achieve this by proper selection of the optimal eigenvalue (shape), by adaption of the area term in the Laplacian operator (size), and by adding special constraints to the Laplace eigenproblem (orientation and alignment). By solving a generalized eigen-problem we can generate a scalar field on the mesh whose Morse-Smale complex is of high quality and satisfies all the user requirements. The final quadrilateral mesh is generated from the Morse-Smale complex by computing a globally smooth parametrization. Here we additionally introduce edge constraints to preserve user specified feature lines accurately.
A virtual restoration stage for real-world objects
Authors: Aliaga Daniel G. , Law Alvin J. , Yeung Yu Hong
Published: December 2008

In this paper, we introduce a system to virtually restore damaged or historically significant objects without needing to physically change the object in any way. Our work addresses both creating a restored synthetic version of the object as viewed from a camera and projecting the necessary light, using digital projectors, to give the illusion of the object being restored. The restoration algorithm uses an energy minimization method to enforce a set of criteria over the surface of the object and provides an interactive tool to the user which can compute a restoration in a few minutes. The visual compensation method develops a formulation that is particularly concerned with obtaining bright compensations under a specified maximum amount of light. The bound on the amount of light is of crucial importance when viewing and restoring old and potentially fragile objects. Finally, we demonstrate our system by restoring several deteriorated and old objects enabling the observer to view the original or restored object at will.
Intrinsic colorization
Authors: Liu Xiaopei , Wan Liang , Qu Yingge , Wong Tien-Tsin , Lin Stephen , Leung Chi-Sing , Heng Pheng-Ann
Published: December 2008

In this paper, we present an example-based colorization technique robust to illumination differences between grayscale target and color reference images. To achieve this goal, our method performs color transfer in an illumination-independent domain that is relatively free of shadows and highlights. It first recovers an illumination-independent
intrinsic reflectance image
of the target scene from multiple color references obtained by web search. The reference images from the web search may be taken from different vantage points, under different illumination conditions, and with different cameras. Grayscale versions of these reference images are then used in decomposing the grayscale target image into its intrinsic reflectance and illumination components. We transfer color from the color reflectance image to the grayscale reflectance image, and obtain the final result by relighting with the illumination component of the target image. We demonstrate via several examples that our method generates results with excellent color consistency.
Fast image/video upsampling
Authors: Shan Qi , Li Zhaorong , Jia Jiaya , Tang Chi-Keung
Published: December 2008

We propose a simple but effective upsampling method for automatically enhancing the image/video resolution, while preserving the essential structural information. The main advantage of our method lies in a feedback-control framework which faithfully recovers the high-resolution image information from the input data,withoutimposing additional local structure constraints learned from other examples. This makes our method independent of the quality and number of the selected examples, which are issues typical of learning-based algorithms, while producing high-quality results without observable unsightly artifacts. Another advantage is that our method naturally extends to video upsampling, where the temporal coherence is maintained automatically. Finally, our method runs very fast. We demonstrate the effectiveness of our algorithm by experimenting with different image/video data.
Richness-preserving manga screening
Authors: Qu Yingge , Pang Wai-Man , Wong Tien-Tsin , Heng Pheng-Ann
Published: December 2008

Due to the tediousness and labor intensive cost, some manga artists have already employed computer-assisted methods for converting color photographs to manga backgrounds. However, existing bitonal image generation methods usually produce unsatisfactory uniform screening results that are not consistent with traditional mangas, in which the artist employs a rich set of screens. In this paper, we propose a novel method for generating bitonal manga backgrounds from color photographs. Our goal is to preserve the visual richness in the original photograph by utilizing not only screen density, but also the variety of screen patterns. To achieve the goal, we select screens for different regions in order to preserve the tone similarity, texture similarity, and chromaticity distinguishability. The multi-dimensional scaling technique is employed in such a color-to-pattern matching for maintaining pattern dissimilarity of the screens. Users can control the mapping by a few parameters and interactively fine-tune the result. Several results are presented to demonstrate the effectiveness and convenience of the proposed method.
Demarcating curves for shape illustration
Authors: Kolomenkin Michael , Shimshoni Ilan , Tal Ayellet
Published: December 2008

Curves on objects can convey the inherent features of the shape. This paper defines a new class of view-independent curves, denoteddemarcating curves.In a nutshell, demarcating curves are the loci of the "strongest" inflections on the surface. Due to their appealing capabilities to extract and emphasize 3D textures, they are applied to artifact illustration in archaeology, where they can serve as a worthy alternative to the expensive, time-consuming, and biased manual depiction currently used.
Continuous model synthesis
Authors: Merrell Paul , Manocha Dinesh
Published: December 2008

We present a novel method for procedurally modeling large complex shapes. Our approach is general-purpose and takes as input any 3D polyhedral model provided by a user. The algorithm exploits the connectivity between the adjacent boundary features of the input model and computes an output model that has similar connected features and resembles the input. No additional user input is needed to guide the model generation and the algorithm proceeds automatically. In practice, our algorithm is simple to implement and can generate a variety of complex shapes representing buildings, landscapes, and 3D fractal shapes in a few minutes.
Real-time control of physically based simulations using gentle forces
Authors: Barbič Jernej , Popović Jovan
Published: December 2008

Recent advances have brought real-time physically based simulation within reach, but simulations are still difficult to control in real time. We present interactive simulations of passive systems such as deformable solids or fluids that are not only fast, but also directable: they follow given input trajectories while simultaneously reacting to user input and other unexpected disturbances. We achieve such directability using a real-time controller that runs in tandem with a real-time physically based simulation. To avoid stiff and over-controlled systems where the natural dynamics are overpowered, the injection of control forces has to be minimized. This search for gentle forces can be made tractable in real-time by linearizing the system dynamics around the input trajectory, and then using a time-varying linear quadratic regulator to build the controller. We show examples of controlled complex deformable solids and fluids, demonstrating that our approach generates a requested fixed outcome for reasonable user inputs, while simultaneously providing runtime motion variety.
Living machines
Authors: Kroeker Kirk L.
Published: December 2008

Researchers of molecular computing and communication are focusing on the type of breakthroughs needed to make the vision of ultrasmall, biocompatible computers a reality
.
Upwardly mobile
Authors: Greengard Samuel
Published: December 2008

Mobile phones are bridging the digital divide and transforming many economic, social, and medical realities, particularly in developing nations
.
Making a difference
Authors: Hoffmann Leah
Published: December 2008

The Grace Hopper Celebration featured technical talks, workshops, networking events, and lively discussions about increasing the number of women in computer science
.
InterviewDatabase dialogue with Pat Selinger
Authors: Hamilton James , Selinger Pat
Published: December 2008

Relational database pioneer Patricia G. Selinger explores the vast realm of database technology and trends in a wide-ranging discussion with Microsoft's James Hamilton
.
PuzzledSolutions and sources
Authors: Winkler Peter
Published: December 2008

Last month (November 2008, p. 112) we posed a trio of brain teasers concerning circular food shapes. Here, we offer some possible solutions. How did you do?
Future Tense: Pester power
Authors: Doctorow Cory
Published: December 2008

Future Tense, one of the revolving features on this page, presents stories from the intersection of computational science and technological speculation, their boundaries limited only by our ability to imagine what will and could be.
Authoring, viewing, and generating hypervideo
Authors: Shipman Frank , Girgensohn Andreas , Wilcox Lynn
Published: December 2008

Hyper-Hitchcock consists of three components for creating and viewing a form of interactive video called detail-on-demand video: a hypervideo editor, a hypervideo player, and algorithms for automatically generating hypervideo summaries. Detail-on-demand video is a form of hypervideo that supports one hyperlink at a time for navigating between video sequences. The Hyper-Hitchcock editor enables authoring of detail-on-demand video without programming and uses video processing to aid in the authoring process. The Hyper-Hitchcock player uses labels and keyframes to support navigation through and back hyperlinks. Hyper-Hitchcock includes techniques for automatically generating hypervideo summaries of one or more videos that take the form of multiple linear summaries of different lengths with links from the shorter to the longer summaries. User studies on authoring and viewing provided insight into the various roles of links in hypervideo and found that player interface design greatly affects people's understanding of hypervideo structure and the video they access.
Using a Hybrid Convolution Tree Kernel for Semantic Role Labeling
Authors: Che Wanxiang , Zhang Min , Aw AiTi , Tan ChewLim , Liu Ting , Li Sheng
Published: December 2008

As a kind of Shallow Semantic Parsing, Semantic Role Labeling (SRL) is gaining more attention as it benefits a wide range of natural language processing applications. Given a sentence, the task of SRL is to recognize semantic arguments (roles) for each predicate (target verb or noun). Feature-based methods have achieved much success in SRL and are regarded as the state-of-the-art methods for SRL. However, these methods are less effective in modeling structured features. As an extension of feature-based methods, kernel-based methods are able to capture structured features more efficiently in a much higher dimension. Application of kernel methods to SRL has been achieved by selecting the tree portion of a predicate and one of its arguments as feature space, which is named as predicate-argument feature (PAF) kernel. The PAF kernel captures the syntactic tree structure features using convolution tree kernel, however, it does not distinguish between the path structure and the constituent structure. In this article, a hybrid convolution tree kernel is proposed to model different linguistic objects. The hybrid convolution tree kernel consists of two individual convolution tree kernels. They are a Path kernel, which captures predicate-argument link features, and a Constituent Structure kernel, which captures the syntactic structure features of arguments. Evaluations on the data sets of the CoNLL-2005 SRL shared task and the Chinese PropBank (CPB) show that our proposed hybrid convolution tree kernel statistically significantly outperforms the previous tree kernels. Moreover, in order to maximize the system performance, we present a composite kernel through combining our hybrid convolution tree kernel method with a feature-based method extended by the polynomial kernel. The experimental results show that the composite kernel achieves better performance than each of the individual methods and outperforms the best reported system on the CoNLL-2005 corpus when only one syntactic parser is used and on the CPB corpus when automated syntactic parse results and correct syntactic parse results are used respectively.
Utility of hybrid wireless experimentation for evaluation of heterogeneous wireless architectures and cross-layer protocols
Authors: Marina Mahesh K. , Xu Zhiguo , Zhou Junlan , Bagrodia Rajive
Published: December 2008

We consider hybrid wireless experimentation, which has emerged as an alternative and complementary methodology to physical experimentation and simulation for wireless network evaluation. Specifically, our focus in this paper is on WHYNET, a flexible hybrid evaluation framework providing the capability to seamlessly integrate simulated, emulated and physical networks, thereby enabling several ways of realizing a given target wireless network scenario each using physical (operational) and simulated elements in different combinations depending on the evaluation needs and available testbed resources. Using two novel and detailed case studies of WHYNET, we demonstrate the utility of the hybrid approach for realistic, scalable and cost-effective evaluation of heterogeneous wireless network scenarios and cross-layer protocol mechanisms
The ORCHESTRA Collaborative Data Sharing System
Authors: Ives Zachary G. , Green Todd J. , Karvounarakis Grigoris , Taylor Nicholas E. , Tannen Val , Talukdar Partha Pratim , Jacob Marie , Pereira Fernando
Published: December 2008

Sharing structured data today requires standardizing upon a single schema, then mapping and cleaning all of the data. This results in a single queriable mediated data instance. However, for settings in which structured data is being collaboratively authored by a large community, e.g., in the sciences, there is often a lack of consensus about how it should be represented, what is correct, and which sources are authoritative. Moreover, such data is seldom static: it is frequently updated, cleaned, and annotated. The ORCHESTRA collaborative data sharing system develops a new architecture and consistency model for such settings, based on the needs of data sharing in the life sciences. In this paper we describe the basic architecture and implementation of the ORCHESTRA system, and summarize some of the open challenges that arise in this setting.
Paper and proposal reviews
Authors: Korth Henry F. , Bernstein Philip A. , Fernandez Mary , Gruenwald Le , Kolaitis Phokion G. , McKinley Kathryn , Ozsu Tamer
Published: December 2008

At the 2008 Computing Research Association Conference at Snowbird, the authors participated in a panel addressing the issue of paper and proposal reviews. This short paper summarizes the panelists' presentations and audience commentary. It concludes with some observations and suggestions on how we might address this issue in the near-term future.
DB&IR integration
Authors: Amer-Yahia Sihem , Hiemstra Djoerd , Roelleke Thomas , Srivastava Divesh , Weikum Gerhard
Published: December 2008

This paper is based on a five-day workshop on "Ranked XML Querying" that took place in Schloss Dagstuhl in Germany in March 2008 and was attended by 27 people from three different research communities: database systems (DB), information retrieval (IR), and Web. The seminar title was interpreted in an IR-style "andish" sense (it covered also subsets of (Ranking, XML, Querying), with larger sets being favored) rather than the DB-style strictly conjunctive manner. So in essence, the seminar really addressed the integration of DB and IR technologies with Web 2.0 being an important target area.
Statements and intrinsic procedures in consecutive Fortran standards
Authors: Gorelik A. M.
Published: December 2008

This paper contains the tables of statements and intrinsic procedures in consecutive Fortran standards: from Fortran 66 up to Fortran 2003.
Hormone signaling through protein destruction: a lesson from plants
Authors: Tan Xu , Zheng Ning
Published: December 2008

Ubiquitin-dependent protein degradation has emerged as a major pathway regulating eukaryotic biology. By employing a variety of ubiquitin ligases to target specific cellular proteins, the ubiquitin-proteasome system controls physiological processes in a highly regulated fashion. Recent studies on a plant hormone auxin have unveiled a novel paradigm of signal transduction in which ubiquitin ligases function as hormone receptors. Perceived by the F-box protein subunit of the SCFTIR1 ubiquitin ligase, auxin directly promotes the recruitment of a family of transcriptional repressors for ubiquitination, thereby activating extensive transcriptional programs. Structural studies have revealed that auxin functions through a “molecular glue” mechanism to enhance protein-protein interactions with the assistance of another small molecule cofactor, inositol hexakisphosphate. Given the extensive repertoire of similar ubiquitin ligases in eukaryotic cells, this novel and widely adopted hormone-signaling mechanism in plants may also exist in other organisms.
Object Representations in the Temporal Cortex of Monkeys and Humans as Revealed by Functional Magnetic Resonance Imaging
Authors: Bell Andrew H. , Hadj-Bouziane Fadila , Frihauf Jennifer B. , Tootell Roger B. H. , Ungerleider Leslie G.
Published: December 2008

Increasing evidence suggests that the neural processes associated with identifying everyday stimuli include the classification of those stimuli into a limited number of semantic categories. How the neural representations of these stimuli are organized in the temporal lobe remains under debate. Here we used functional magnetic resonance imaging (fMRI) to identify correlates for three current hypotheses concerning object representations in the inferior temporal (IT) cortex of monkeys and humans: representations based on animacy, semantic categories, or visual features. Subjects were presented with blocked images of faces, body parts (animate stimuli), objects, and places (inanimate stimuli), and multiple overlapping contrasts were used to identify the voxels most selective for each category. Stimulus representations appeared to segregate according to semantic relationships. Discrete regions selective for animate and inanimate stimuli were found in both species. These regions could be further subdivided into regions selective for individual categories. Notably, face-selective regions were contiguous with body-part-selective regions, and object-selective regions were contiguous with place-selective regions. When category-selective regions in monkeys were tested with blocks of single exemplars, individual voxels showed preferences for visually dissimilar exemplars from the same category and voxels with similar preferences tended to cluster together. Our results provide some novel observations with respect to how stimulus representations are organized in IT cortex. In addition, they further support the idea that representations of complex stimuli in IT cortex are organized into multiple hierarchical tiers, encompassing both semantic and physical properties.
Glutamatergic Nonpyramidal Neurons From Neocortical Layer VI and Their Comparison With Pyramidal and Spiny Stellate Neurons
Authors: Andjelic Sofija , Gallopin Thierry , Cauli Bruno , Hill Elisa L. , Roux Lisa , Badr Sammy , Hu Emilie , Tamás Gábor , Lambolez Bertrand
Published: December 2008

The deeper part of neocortical layer VI is dominated by nonpyramidal neurons, which lack a prominent vertically ascending dendrite and predominantly establish corticocortical connections. These neurons were studied in rat neocortical slices using patch-clamp, single-cell reverse transcription–polymerase chain reaction, and biocytin labeling. The majority of these neurons expressed the vesicular glutamate transporter but not glutamic acid decarboxylase, suggesting that a high proportion of layer VI nonpyramidal neurons are glutamatergic. Indeed, they exhibited numerous dendritic spines and established asymmetrical synapses. Our sample of glutamatergic nonpyramidal neurons displayed a wide variety of somatodendritic morphologies and a subset of these cells expressed the Nurr1 mRNA, a marker for ipsilateral, but not commissural corticocortical projection neurons in layer VI. Comparison with spiny stellate and pyramidal neurons from other layers showed that glutamatergic neurons consistently exhibited a low occurrence of GABAergic interneuron markers and regular spiking firing patterns. Analysis of electrophysiological diversity using unsupervised clustering disclosed three groups of cells. Layer V pyramidal neurons were segregated into a first group, whereas a second group consisted of a subpopulation of layer VI neurons exhibiting tonic firing. A third heterogeneous cluster comprised spiny stellate, layer II/III pyramidal, and layer VI neurons exhibiting adaptive firing. The segregation of layer VI neurons in two different clusters did not correlate either with their somatodendritic morphologies or with Nurr1 expression. Our results suggest that electrophysiological similarities between neocortical glutamatergic neurons extend beyond layer positioning, somatodendritic morphology, and projection specificity.
Reduction in ovulation or male sex phenotype increases long-term anoxia survival in adaf-16-independent manner inCaenorhabditis elegans
Authors: Mendenhall Alexander R. , LeBlanc Michelle G. , Mohan Desh P. , Padilla Pamela A.
Published: December 2008

Identifying genotypes and phenotypes that enhance an organism's ability to survive stress is of interest. We used Caenorhabditis elegans mutants, RNA interference (RNAi), and the chemical 5-fluorodeoxyuridine (FUDR) to test the hypothesis that a reduction in progeny would increase oxygen deprivation (anoxia) survival. In the hermaphrodite gonad, germ line processes such as spermatogenesis and oogenesis can be simultaneously as well as independently disrupted by genetic mutations. We analyzed genetic mutants [ glp-1(q158), glp-4(bn2ts), plc-1(rx1), ksr-1(ku68), fog-2(q71), fem-3(q20), spe-9(hc52ts), fer-15(hc15ts)] with reduced progeny production due to various reproductive defects. Furthermore, we used RNAi to inhibit the function of gene products in the RTK/Ras/MAPK signaling pathway, which is known to be involved in a variety of developmental processes including gonad function. We determined that reduced progeny production or complete sterility enhanced anoxia survival except in the case of sterile hermaphrodites [ spe-9(hc52ts), fer-15(hc15ts)] undergoing oocyte maturation and ovulation as exhibited by the presence of laid unfertilized oocytes. Furthermore, the fog-2(q71) long-term anoxia survival phenotype was suppressed when oocyte maturation and ovulation were induced by mating with males that have functional or nonfunctional sperm. The mutants with a reduced progeny production survive long-term anoxia in a daf-16- and hif-1-independent manner. Finally, we determined that wild-type males were able to survive long-term anoxia in a daf-16-independent manner. Together, these results suggest that the insulin signaling pathway is not the only mechanism to survive oxygen deprivation and that altering gonad function, in particular oocyte maturation and ovulation, leads to a physiological state conducive for oxygen deprivation survival.
Probiotic Bacteria Influence the Composition and Function of the Intestinal Microbiota
Authors: O'Toole Paul W. , Cooney Jakki C.
Published: December 2008

Probiotics have a range of proposed health benefits for the consumer, which may include modulating the levels of beneficial elements in the microbiota. Recent investigations using molecular approaches have revealed a human intestinal microbiota comprising over 1000 phylotypes. Mechanisms whereby probiotics impact on the intestinal microbiota include competition for substrates, direct antagonism by inhibitory substances, competitive exclusion, and potentially host-mediated effects such as improved barrier function and altered immune response. We now have the microbial inventories and genetic blueprints to begin tackling intestinal microbial ecology at an unprecedented level of detail, aided by the understanding that dietary components may be utilized differentially by individual phylotypes. Controlled intervention studies in humans, utilizing latest molecular technologies, are required to consolidate evidence for bacterial species that impact on the microbiota. Mechanistic insights should be provided by metabolomics and other analytical techniques for small molecules. Rigorous characterization of interactions between the diet, microbiota, and probiotic bacteria will provide new opportunities for modulating the microbiota towards improving human health.
Convergence to Common Fixed Point for Generalized Asymptotically Nonexpansive Semigroup in Banach Spaces
Authors: Li Yali , Liu Jianjun , Deng Lei
Published: December 2008

Let K be a nonempty closed convex subset of a reflexive and strictly convex Banach
space E with a uniformly Gâteaux differentiable norm, ℱ = {T(h) : h ≥ 0} a generalized asymptotically
nonexpansive self‐mapping semigroup of K, and f : K → K a fixed contractive mapping
with contractive coefficient β ∈ (0, 1). We prove that the following implicit and modified implicit
viscosity iterative schemes {xn} defined by xn = αnf(xn) + (1 − αn)T(tn)xn and xn = αnyn + (1 − αn)T(tn)xn,yn = βnf(xn−1) + (1 − βn)xn−1 strongly converge to p ∈ F as n → ∞ and p is the unique solution to the following variational
inequality: 〈f(p) − p, j(y − p)〉 ≤ 0 for all y ∈ F.
Experimental Active Vibration Control in Truss Structures Considering Uncertainties in System Parameters
Authors: Bueno Douglas Domingues , Marqui Clayton Rodrigo , Santos Rodrigo Borges , Neto Camilo Mesquita , Lopes Vicente
Published: December 2008

This paper deals with the study of algorithms for robust active vibration control in flexible structures considering uncertainties in system parameters. It became an area of enormous interest, mainly due to the countless demands of optimal performance in mechanical systems as aircraft, aerospace, and automotive structures. An important and difficult problem for designing active vibration control is to get a representative dynamic model. Generally, this model can be obtained using finite element method (FEM) or an identification method using experimental data. Actuators and sensors may affect the dynamics properties of the structure, for instance, electromechanical coupling of piezoelectric material must be considered in FEM formulation for flexible and lightly damping structure. The nonlinearities and uncertainties involved in these structures make it a difficult task, mainly for complex structures as spatial truss structures. On the other hand, by using an identification method, it is possible to obtain the dynamic model represented through a state space realization considering this coupling. This paper proposes an experimental methodology for vibration control in a 3D truss structure using PZT wafer stacks and a robust control algorithm solved by linear matrix inequalities.
Spontaneous Regression of Pulmonary Metastases from Breast Angiosarcoma
Authors: Kim S. W. , Wylie J.
Published: December 2008

Spontaneous regression of cancer is a rare phenomenon. We present a rare case of pulmonary metastases in a 72-year-old woman with metastatic breast angiosarcoma. She was diagnosed with a breast angiosarcoma in 2005 and underwent a total mastectomy and postoperative radiotherapy. Unfortunately, a year later she was found to have multiple lung and scalp metastases but in a view of her poor general fitness, she was not a candidate for chemotherapy and was kept on regular followup. Despite the absence of any treatment, the followup chest X-ray showed a significant reduction in the number and size of lung nodules and her scalp lesions regressed completely. Seven months after the diagnosis of metastatic disease, the nodules in her scalp remain controlled.
Characteristics of Primary Amphetamine Users in Sweden: A Criminal Justice Population Examined with the Addiction Severity Index
Authors: Hakansson A. , Schlyter F. , Berglund M.
Published: December 2008

Background/Aims: Characteristics of primary amphetamine, heroin and cocaine users were compared in a criminal justice population. Methods: 7,085 clients with suspected or reported substance use were studied using the Addiction Severity Index. Variables separating amphetamine, heroin and cocaine users were analyzed in stepwise logistic regression. Results: There were considerably more primary amphetamine users (n = 1,396) than heroin (n = 392) and cocaine (n = 119) users. Amphetamine users were older, a more rural population, and less likely to be non-Nordic immigrants. Compared with heroin, amphetamine use was associated with older age, Nordic origin, nonurban residence, memory/concentration problems, parental alcohol problems, and less history of other opioid use, overdose and detoxification. Compared with cocaine, amphetamine use was associated with older age, Nordic origin, nonurban residence, injecting, tobacco and institution treatment. Overlap of drug use between groups was relatively uncommon. Conclusion: This pattern of amphetamine use, common among Swedish criminals, has relatively distinct boundaries from heroin and cocaine use, commonly involves injecting, and differs from other countries. Psychiatric problems and alcohol heredity were common, and evidence-based treatment for amphetamine users is needed. The connection between amphetamine use and criminal behavior is insufficiently understood and should be further addressed.
The Social Costs of Alcohol Misuse in Estonia
Authors: Saar Indrek
Published: December 2008

The aim of this study was to estimate the social costs of alcohol misuse in Estonia in 2006. Using a prevalence-based cost-of-illness approach, both direct and indirect costs were considered, including tangible costs associated with health care, criminal justice, rescue services, damage to property, premature mortality, incarceration, incapability of working due to illnesses, and lower labor productivity. The results show that alcohol misuse cost Estonia more than EUR 200 million in 2006. The costs involved are estimated to represent 1.6% of the gross domestic product (GDP), which is relatively high in comparison with many other countries. In addition, the state receives less receipts from the alcohol excise tax than the costs that it incurs as a consequence of alcohol misuse, which points to the existence of economic inefficiency with respect to the alcohol market. The results of this study suggest that there is definitely a need for further cost-benefit analysis to reach a conclusion regarding the possible utility of government intervention.
Kimura Disease: A Case Report and Review of the Chinese Literature
Authors: Wang D.Y. , Mao J.H. , Zhang Y. , Gu W.Z. , Zhao S.A. , Chen Y.F. , Liu A.M.
Published: December 2008

Background: Kimura disease, often accompanied by nephrotic syndrome, is a rare, chronic inflammatory disorder of unknown cause. In this report, the clinical and histopathological characteristics of 20 Chinese patients with Kimura disease-associated nephrotic syndrome were retrospectively evaluated. Methods: We report a case of Kimura disease that was diagnosed recently in our ward, with steroid-responsive but recurrent minimal-change nephrotic syndrome. Meanwhile, we also used three powerful Chinese journal search engines (Cqvip.com, Wanfang.data and ScienceChina) to search the cases reported in Chinese from 1984 to 2007. Results: The nephrotic syndrome of our patient occurred 20 months after the onset of Kimura disease. Renal biopsy revealed minimal-change lesions. The patient was responsive to the steroid, but proteinuria recurred. In most of the 19 other cases, the onset of nephrotic syndrome occurred after subcutaneous masses. Renal biopsy in 13 cases showed mesangial proliferative glomerulonephritis in 9, minimal change disease in 2 and membrane nephropathy in 2 cases. Serum creatinine levels were elevated in 5 patients. Conclusion: Normally, Kimura disease-associated nephrotic syndrome patients are sensitive to prednisone therapy but are likely to relapse. In patients with recurrent nephrotic syndrome, renal insufficiency is not uncommon.
Automated Design of Image Operators that Detect Interest Points
Authors: Trujillo Leonardo , Olague Gustavo
Published: December 2008

This work describes how evolutionary computation can be used to synthesize low-level image operators that detect interesting points on digital images. Interest point detection is an essential part of many modern computer vision systems that solve tasks such as object recognition, stereo correspondence, and image indexing, to name but a few. The design of the specialized operators is posed as an optimization/search problem that is solved with genetic programming (GP), a strategy still mostly unexplored by the computer vision community. The proposed approach automatically synthesizes operators that are competitive with state-of-the-art designs, taking into account an operator's geometric stability and the global separability of detected points during fitness evaluation. The GP search space is defined using simple primitive operations that are commonly found in point detectors proposed by the vision community. The experiments described in this paper extend previous results (Trujillo and Olague, 2006a,b) by presenting 15 new operators that were synthesized through the GP-based search. Some of the synthesized operators can be regarded as improved manmade designs because they employ well-known image processing techniques and achieve highly competitive performance. On the other hand, since the GP search also generates what can be considered as unconventional operators for point detection, these results provide a new perspective to feature extraction research.
An Enhanced Memetic Differential Evolution in Filter Design for Defect Detection in Paper Production
Authors: Tirronen Ville , Neri Ferrante , Kärkkäinen Tommi , Majava Kirsi , Rossi Tuomo
Published: December 2008

This article proposes an Enhanced Memetic Differential Evolution (EMDE) for designing digital filters which aim at detecting defects of the paper produced during an industrial process. Defect detection is handled by means of two Gabor filters and their design is performed by the EMDE. The EMDE is a novel adaptive evolutionary algorithm which combines the powerful explorative features of Differential Evolution with the exploitative features of three local search algorithms employing different pivot rules and neighborhood generating functions. These local search algorithms are the Hooke Jeeves Algorithm, a Stochastic Local Search, and Simulated Annealing. The local search algorithms are adaptively coordinated by means of a control parameter that measures fitness distribution among individuals of the population and a novel probabilistic scheme. Numerical results confirm that Differential Evolution is an efficient evolutionary framework for the image processing problem under investigation and show that the EMDE performs well. As a matter of fact, the application of the EMDE leads to a design of an efficiently tailored filter. A comparison with various popular metaheuristics proves the effectiveness of the EMDE in terms of convergence speed, stagnation prevention, and capability in detecting solutions having high performance.
Comparison of Snow Cover from Satellite and Numerical Weather Prediction Models in the Northern Hemisphere and Northern Europe
Authors: Hyvärinen Otto , Eerola Kalle , Siljamo Niilo , Koskinen Jarkko
Published: December 2008

Snow cover has a strong effect on the surface and lower atmosphere in NWP models. Because the progress of in situ observations has stalled, satellite-based snow analyses are becoming increasingly important. Currently, there exist several products that operationally map global or continental snow cover. In this study, satellite-based snow cover analyses from NOAA, NASA, and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), and NWP snow analyses from the High-Resolution Limited-Area Model (HIRLAM) and ECMWF, were compared using data from January to June 2006. Because no analyses were independent and since available in situ measurements were already used in the NWP analyses, no independent ground truth was available and only the consistency between analyses could be compared. Snow analyses from NOAA, NASA, and ECMWF were similar, but the analysis from NASA was greatly hampered by clouds. HIRLAM and EUMETSAT deviated most from other analyses. Even though the analysis schemes of HIRLAM and ECMWF were quite similar, the resulting snow analyses were quite dissimilar, because ECMWF used the satellite information of snow cover in the form of NOAA analyses, while HIRLAM used none. The differences are especially prominent in areas around the snow edge where few in situ observations are available. This suggests that NWP snow analyses based only on in situ measurements would greatly benefit from inclusion of satellite-based snow cover information.
Scales of Linear Baroclinic Instability and Macroturbulence in Dry Atmospheres
Authors: Merlis Timothy M. , Schneider Tapio
Published: December 2008

Linear stability analyses are performed on a wide range of mean flows simulated with a dry idealized general circulation model. The zonal length scale of the linearly most unstable waves is similar to the Rossby radius. It is also similar to the energy-containing zonal length scale in statistically steady states of corresponding nonlinear simulations. The meridional length scale of the linearly most unstable waves is generally smaller than the energy-containing meridional length scale in the corresponding nonlinear simulations. The growth rate of the most unstable waves increases with increasing Eady growth rate, but the scaling relationship is not linear in general. The available potential energy and barotropic and baroclinic kinetic energies of the linearly most unstable waves scale linearly with each other, with similar partitionings among the energy forms as in the corresponding nonlinear simulations. These results show that the mean flows in the nonlinear simulations are baroclinically unstable, yet there is no substantial inverse cascade of barotropic eddy kinetic energy from the baroclinic generation scale to larger scales, even in strongly unstable flows. Some aspects of the nonlinear simulations, such as partitionings among eddy energies, can be understood on the basis of linear stability analyses; for other aspects, such as the structure of heat and momentum fluxes, nonlinear modifications of the waves are important.
The Role of Stochastic Forcing in Ensemble Forecasts of the 1997/98 El Niño
Authors: Shi Li , Alves Oscar , Hendon Harry H. , Wang Guomin , Anderson David
Published: December 2008

The impact of stochastic intraseasonal variability on the onset of the 1997/98 El Niño was examined using a large ensemble of forecasts starting on 1 December 1996, produced using the Australian Bureau of Meteorology Predictive Ocean Atmosphere Model for Australia (POAMA) seasonal forecast coupled model. This coupled model has a reasonable simulation of El Niño and the Madden–Julian oscillation, so it provides an ideal framework for investigating the interaction between the MJO and El Niño. The experiment was designed so that the ensemble spread was simply a result of internal stochastic variability that is generated during the forecast. For the initial conditions used here, all forecasts led to warm El Niño–type conditions with the amplitude of the warming varying from 0.5° to 2.7°C in the Niño-3.4 region.

All forecasts developed an MJO event during the first 4 months, indicating that perhaps the background state favored MJO development. However, the details of the MJOs that developed during December 1996–March 1997 had a significant impact on the subsequent strength of the El Niño event. In particular, the forecasts with the initial MJOs that extended farther into the central Pacific, on average, led to a stronger El Niño, with the westerly winds in the western Pacific associated with the MJO leading the development of SST and thermocline anomalies in the central and eastern Pacific. These results imply a limit to the accuracy with which the strength of El Niño can be predicted because the details of individual MJO events matter. To represent realistic uncertainty, coupled models should be able to represent the MJO, including its propagation into the central Pacific so that forecasts produce sufficient ensemble spread.
Lifetime of Anthropogenic Climate Change: Millennial Time Scales of Potential CO2 and Surface Temperature Perturbations
Authors: Eby M. , Zickfeld K. , Montenegro A. , Archer D. , Meissner K. J. , Weaver A. J.
Published: December 2008

Multimillennial simulations with a fully coupled climate–carbon cycle model are examined to assess the persistence of the climatic impacts of anthropogenic CO2 emissions. It is found that the time required to absorb anthropogenic CO2 strongly depends on the total amount of emissions; for emissions similar to known fossil fuel reserves, the time to absorb 50% of the CO2 is more than 2000 yr. The long-term climate response appears to be independent of the rate at which CO2 is emitted over the next few centuries. Results further suggest that the lifetime of the surface air temperature anomaly might be as much as 60% longer than the lifetime of anthropogenic CO2 and that two-thirds of the maximum temperature anomaly will persist for longer than 10 000 yr. This suggests that the consequences of anthropogenic CO2 emissions will persist for many millennia.
Neural Networks Applied to Estimating Subglacial Topography and Glacier Volume
Authors: Clarke Garry K. C. , Berthier Etienne , Schoof Christian G. , Jarosch Alexander H.
Published: December 2008

To predict the rate and consequences of shrinkage of the earth’s mountain glaciers and ice caps, it is necessary to have improved regional-scale models of mountain glaciation and better knowledge of the subglacial topography upon which these models must operate. The problem of estimating glacier ice thickness is addressed by developing an artificial neural network (ANN) approach that uses calculations performed on a digital elevation model (DEM) and on a mask of the present-day ice cover. Because suitable data from real glaciers are lacking, the ANN is trained by substituting the known topography of ice-denuded regions adjacent to the ice-covered regions of interest, and this known topography is hidden by imagining it to be ice-covered. For this training it is assumed that the topography is flooded to various levels by horizontal lake-like glaciers. The validity of this assumption and the estimation skill of the trained ANN is tested by predicting ice thickness for four 50 km × 50 km regions that are currently ice free but that have been partially glaciated using a numerical ice dynamics model. In this manner, predictions of ice thickness based on the neural network can be compared to the modeled ice thickness and the performance of the neural network can be evaluated and improved. From the results, thus far, it is found that ANN depth estimates can yield plausible subglacial topography with a representative rms elevation error of ±70 m and remarkably good estimates of ice volume.