bluuebunny/crossref_metadata_2025 huggingface dataset:
Three‐dimensional tracking of cardiac catheters using an inverse geometry x‐ray fluoroscopy system
Authors: Speidel Michael A. , Tomkowiak Michael T. , Raval Amish N. , Van Lysel Michael S.
Published: December 2010

Purpose:

Scanning beam digital x‐ray (SBDX) is an inverse geometry fluoroscopic system with high dose efficiency and the ability to perform continuous real‐time tomosynthesis at multiple planes. This study describes a tomosynthesis‐based method for 3D tracking of high‐contrast objects and present the first experimental investigation of cardiac catheter tracking using a prototype SBDX system.

Methods:

The 3D tracking algorithm utilizes the stack of regularly spaced tomosynthetic planes that are generated by SBDX after each frame period (15 frames/s). Gradient‐filtered versions of the image planes are generated, the filtered images are segmented into object regions, and then a 3D coordinate is calculated for each object region. Two phantom studies of tracking performance were conducted. In the first study, an ablation catheter in a chest phantom was imaged as it was pulled along a 3D trajectory defined by a catheter sheath (10, 25, and 50 mm/s pullback speeds). SBDX tip tracking coordinates were compared to the 3D trajectory of the sheath as determined from a CT scan of the phantom after the registration of the SBDX and CT coordinate systems. In the second study, frame‐to‐frame tracking precision was measured for six different catheter configurations as a function of image noise level ( mean detected x‐ray fluence at isocenter).

Results:

During catheter pullbacks, the 3D distance between the tracked catheter tip and the sheath centerline was (mean standard deviation). The electrode to centerline distances were comparable to the diameter of the catheter tip (2.3 mm), the confining sheath (4 mm outside diameter), and the estimated SBDX‐to‐CT registration error . The tip position was localized for all 332 image frames analyzed and 83% of tracked positions were inside the 3D sheath volume derived from CT. The pullback speeds derived from the catheter trajectories were within 5% of the programed pullback speeds. The tracking precision of ablation and diagnostic catheter tips ranged from at the highest image fluence to at the lowest fluence. Tracking precision depended on image fluence, the size of the tracked catheter electrode, and the contrast of the electrode.

Conclusions:

High speed multiplanar tomosynthesis with an inverse geometry x‐ray fluoroscopy system enables 3D tracking of multiple high‐contrast objects at the rate of fluoroscopic imaging. The SBDX system is capable of tracking electrodes in standard cardiac catheters with approximately 1 mm accuracy and precision.
Automatic anatomy recognition via multiobject oriented active shape models
Authors: Chen Xinjian , Udupa Jayaram K. , Alavi Abass , Torigian Drew A.
Published: December 2010

Purpose:

This paper studies the feasibility of developing an automatic anatomy recognition (AAR) system in clinical radiology and demonstrates its operation on clinical 2D images.

Methods:

The anatomy recognition method described here consists of two main components: (a) multiobject generalization of OASM and (b) object recognition strategies. The OASM algorithm is generalized to multiple objects by including a model for each object and assigning a cost structure specific to each object in the spirit of live wire. The delineation of multiobject boundaries is done in MOASM via a three level dynamic programming algorithm, wherein the first level is at pixel level which aims to find optimal oriented boundary segments between successive landmarks, the second level is at landmark level which aims to find optimal location for the landmarks, and the third level is at the object level which aims to find optimal arrangement of object boundaries over all objects. The object recognition strategy attempts to find that pose vector (consisting of translation, rotation, and scale component) for the multiobject model that yields the smallest total boundary cost for all objects. The delineation and recognition accuracies were evaluated separately utilizing routine clinical chest CT, abdominal CT, and foot MRI data sets. The delineation accuracy was evaluated in terms of true and false positive volume fractions (TPVF and FPVF). The recognition accuracy was assessed (1) in terms of the size of the space of the pose vectors for the model assembly that yielded high delineation accuracy, (2) as a function of the number of objects and objects' distribution and size in the model, (3) in terms of the interdependence between delineation and recognition, and (4) in terms of the closeness of the optimum recognition result to the global optimum.

Results:

When multiple objects are included in the model, the delineation accuracy in terms of TPVF can be improved to 97%–98% with a low FPVF of 0.1%–0.2%. Typically, a recognition accuracy of yielded a TPVF and FPVF . Over the three data sets and over all tested objects, in 97% of the cases, the optimal solutions found by the proposed method constituted the true global optimum.

Conclusions:

The experimental results showed the feasibility and efficacy of the proposed automatic anatomy recognition system. Increasing the number of objects in the model can significantly improve both recognition and delineation accuracy. More spread out arrangement of objects in the model can lead to improved recognition and delineation accuracy. Including larger objects in the model also improved recognition and delineation. The proposed method almost always finds globally optimum solutions.
Computerized quantitative evaluation of mammographic accreditation phantom images
Authors: Lee Yongbum , Tsai Du‐Yih , Shinohara Norimitsu
Published: December 2010

Purpose:

The objective was to develop and investigate an automated scoring scheme of the American College of Radiology (ACR) mammographic accreditation phantom (RMI 156, Middleton, WI) images.

Methods:

The developed method consisted of background subtraction, determination of region of interest, classification of fiber and mass objects by Mahalanobis distance, detection of specks by template matching, and rule‐based scoring. Fifty‐one phantom images were collected from 51 facilities for this study (one facility provided one image). A medical physicist and two radiologic technologists also scored the images. The human and computerized scores were compared.

Results:

In terms of meeting the ACR's criteria, the accuracies of the developed method for computerized evaluation of fiber, mass, and speck were 90%, 80%, and 98%, respectively. Contingency table analysis revealed significant association between observer and computer scores for microcalcifications but not for masses and fibers.

Conclusions:

The developed method may achieve a stable assessment of visibility for test objects in mammographic accreditation phantom image in whether the phantom image meets the ACR's criteria in the evaluation test, although there is room left for improvement in the approach for fiber and mass objects.
Commissioning Siemens Virtual Wedges in the Oncentra MasterPlan treatment planning system using Gafchromic EBT film
Authors: Ferretti A. , Simonato F. , Zandonà R. , Reccanello S. , Fabbris R.
Published: December 2010

Purpose:

Virtual Wedges™ were introduced in Siemens LINACs to improve the treatment workflow. The aim of the present work is the validation of dose calculation by MasterPlan‐Oncentra treatment planning system for virtual wedged beams.

Methods:

The Oncor Siemens accelerator installed in the authors' department produces 6 and 15 MV photon beams. At first, the consistency of VW LINAC production was tested and the EBT film measuring method was verified. This method is based on the scanner uniformity correction and absolute dose calibration as reported in literature. Then, the measured and calculated wedge factors and beam profiles are compared. For 15°, 30°, 45°, and 60° wedge angles, the wedge factors for different field sizes were measured by an ionization chamber and the dose profiles were acquired by Gafchromic EBT film. Both types of measurements were collected in isocentric condition.

Results:

The comparison between measured and calculated VW factors shows discrepancies that increase with field size and angle. The OTP Enhanced algorithm produces better agreement with measurements than the Classic one, with improvement overall visible for large angles. The agreement between measured and planned beam profiles is within limits reported by the ESTRO Booklet No. 7 in terms of confidence limits.

Conclusions:

The MasterPlan‐Oncentra treatment planning system determines wedge factors and VW profiles within the requested accuracy in the majority of treatment conditions. For big field dimensions and wedge angle, wedge factor accordance was worse, but it may be increased with an improvement of the LINAC dosimetric board calibration.
Direct three‐dimensional coherently scattered x‐ray microtomography
Authors: Cui Congwu , Jorgensen Steven M. , Eaker Diane R. , Ritman Erik L.
Published: December 2010

Purpose:

It has been shown that coherently scattered x rays can be used to discriminate and identify specific components in a mixture of low atomic weight materials. The authors demonstrated a new method of doing coherently scattered x‐ray tomography with a thin sheet of x ray.

Methods:

A collimated x‐ray fan‐beam, a parallel polycapillary collimator, and a phantom consisting of several biocompatible materials of low attenuation‐based contrast were used to investigate the feasibility of the method. Because of the particular experimental setup, only the phantom translation perpendicular to the x‐ray beam is needed and, thus, there is no need of Radon‐type tomographic reconstruction, except for the correction of the attenuation to the primary and scattered x rays, which was performed by using a conventional attenuation‐based tomographic image data set. The coherent scatter image contrast changes with momentum transfer among component materials in the specimen were investigated with multiple x‐ray sources with narrow bandwidth spectra generated with anode and filter combinations of Cu/Ni (8 keV), Mo/Zr (18 keV), and Ag/Pd (22 keV) and at multiple scatter angles by orienting the detector and polycapillary collimator at different angles to the illuminating x ray.

Results:

The contrast among different materials changes with the x‐ray source energy and the angle at which the image was measured. The coherent scatter profiles obtained from the coherent scatter images are consistent with the published results.

Conclusions:

This method can be used to directly generate the three‐dimensional coherent scatter images of small animal, biopsies, or other small objects with low atomic weight biological or similar synthetic materials with low attenuation contrast. With equipment optimized, submillimeter spatial resolution may be achieved.
An algorithm for fast beam angle selection in intensity modulated radiotherapy
Authors: Vaitheeswaran R. , Sathiya Narayanan V. K. , Bhangle Janhavi R. , Nirhali Amit , Kumar Namitha , Basu Sumit , Maiya Vikram
Published: December 2010

Purpose:

This article aims to introduce a novel algorithm for fast beam angle selection in intensity modulated radiotherapy (IMRT).

Methods:

The algorithm models the optimization problem as a beam angle ranking problem and chooses suitable beam angles according to their rank. A new parameter called “beam intensity profile perturbation score (BIPPS)” is used for ranking the beam angles. The BIPPS‐based beam angle ranking implicitly accounts for the dose‐volume effects of the involved structures. A simulated phantom case with obvious optimal beam angles is used to verify the validity of the presented technique. In addition, the efficiency of the algorithm was examined in three clinical cases (prostate, pancreas, and head and neck) in terms of DVH and dose distribution. In all cases, the judgment of the algorithm's efficiency was based on the comparison between plans with equidistant beams (equal‐angle‐plan) and plans with beams obtained using the algorithm (suitable‐angle‐plan).

Results:

It is observed from the study that the beam angle ranking function over BIPPS instantly picks up a suitable set of beam angles for a specific case. It takes only about 15 min for choosing the suitable beam angles even for the most complicated cases. The DVHs and dose distributions confirm that the proposed algorithm can efficiently reduce the mean or maximum dose to OARs, while guaranteeing the target coverage and dose uniformity. On the average, about 17% reduction in the mean dose to critical organs, such as rectum, bladder, kidneys and parotids, is observed. Also, about 12% (averaged) reduction in the maximum dose to critical organs (spinal cord) is observed in the clinical cases presented in this study.

Conclusions:

This study demonstrates that the algorithm can be effectively applied to IMRT scenarios to get fast and case specific beam angle configurations.
The Extracellular Domain of Fibroblast Growth Factor Receptor 3 Inhibits Ligand-Independent Dimerization
Authors: Chen Lirong , Placone Jesse , Novicky Lawrence , Hristova Kalina
Published: December 2010

The extracellular domain of a receptor tyrosine kinase has opposing effects on dimerization depending on whether ligand is present.
Zap70 as an Adaptor
Authors: Wong Wei
Published: December 2010

The tyrosine kinase Zap70 has kinase-independent functions during T cell activation.
Dephosphorylation to Die For
Authors: Ray L. Bryan
Published: December 2010

Induction of apoptosis requires dephosphorylation of a regulatory protein in the mitochondrial outer membrane.
Lynx Vision
Authors: Hines Pamela J.
Published: December 2010

A gene identified in the mouse may show the way to improved treatments for amblyopia, a condition of indistinct vision.
Cellular Devices
Authors: Ray L. Bryan
Published: December 2010

Cells engineered to detect a cancer-associated marker produce a protein that sensitizes them to an anticancer drug.
Compartment-Specific Control of Signaling from a DNA-Sensing Immune Receptor
Authors: Engel Alex , Barton Gregory M.
Published: December 2010

The endosomal compartment in which TLR9 is activated determines which cytokines are produced.
Replacing the Enzyme α-
l
-Iduronidase at Birth Ameliorates Symptoms in the Brain and Periphery of Dogs with Mucopolysaccharidosis Type I
Authors: Dierenfeld Ashley D. , McEntee Michael F. , Vogler Carole A. , Vite Charles H. , Chen Agnes H. , Passage Merry , Le Steven , Shah Sahil , Jens Jackie K. , Snella Elizabeth M. , Kline Karen L. , Parkes Jennifer D. , Ware Wendy A. , Moran Lori E. , Fales-Williams Amanda J. , Wengert Jane A. , Whitley R. David , Betts Daniel M. , Boal Amy M. , Riedesel Elizabeth A. , Gross William , Ellinwood N. Matthew , Dickson Patricia I.
Published: December 2010

Replacing the enzyme α-
l
-iduronidase at birth ameliorates symptoms in the brain and periphery of dogs with mucopolysaccharidosis type I.
Don’t Bother Me
Authors: Minzenberg Michael J.
Published: December 2010

Methylation of the
corticotrophin-releasing factor
gene is associated with resilience to stressful events in adult mice.
Two Pluses Make a Minus
Authors: Morozov Alexei
Published: December 2010

Erythropoietin decreases the positive effects of trastuzumab in breast cancer patients.
HYDRATION RECOVERY OF CANINE THYROARYTENOID MUSCLE TISSUE AFTER VARYING LEVELS OF DEHYDRATION
Authors: YANG YEXING , JIANG JACK J.
Published: December 2010

We observed and calculated the solid and liquid volumes and mass parameters of canine vocal fold thyroarytenoid (TA) muscle at tissue dehydration levels of 30% and 70% followed by a complete rehydration to examine the effects of hydration recovery with respect to biphasic properties of the TA muscle in relation to the vocal fold lamina propria. Twenty samples of TA muscle were harvested from 10 canine larynges. Each sample group was subjected to either 30% or 70% dehydration. Following dehydration, the samples rehydrated until the tissue mass stabilized. The solid volume and mass fraction, liquid volume and mass fraction, liquid–solid volume and mass ratios, and degree of hydration recovery were calculated. Median liquid–solid volume ratios were significantly different between the 30% and 70% groups after rehydration and between the medians of 30% and 70% liquid–solid mass ratios after rehydration. The means of solid mass fraction, liquid mass fraction, solid volume fraction, and liquid volume fraction all displayed statistically significant differences. Irreversible tissue damage undergone via severe dehydration of the TA muscle indicates the anatomical and physiological similarity between the TA muscle and the lamina propria. The results imply the significance of the biphasic theory in the construction of biomechanical models.
ADAPTIVE SEGMENTATION OF MEDICAL MR IMAGES BASED ON BIAS CORRECTION
Authors: FU ZENGLIANG , SU YONGLIN , YE MING , LIN YANPING , WANG CHENGTAO
Published: December 2010

A two-phase model is introduced to extract clinically useful information from medical MR images. In the preprocessing phase, a refined bias correction method is adopted to reduce the influence of intensity inhomogeneity by removing the bias field, which paves the way for improving the subsequent segmentation accuracy. During image segmentation process, a novel adaptive level set technique is designed to capture the boundary of desired region. By virtue of adaptive driving term, the external force automatically changes its propagating direction when evolving curve goes through object boundary, which effectively prevents the final results deviating from correct position. Moreover, insensitivity to initial contour also enables its automatic applications. Experiments on synthetic and real MR images demonstrate the feasibility and robustness of the proposed method.
PERFECT POPULATION TRANSFER IN PULSE-DRIVEN QUANTUM CHAINS
Authors: CHEN XIN , WANG YAOXIONG , GE YUNJIAN , SHI JUNHUI , RABITZ HERSCHEL , SHUANG FENG
Published: December 2010

The quantum dynamics of a pulse-driven finite-dimensional quantum chain with only nearest-neighbor coupling is studied. We extend the concept of Rabi oscillations from two-level quantum systems to the multi-level quantum chains. The time-dependent quantum dynamics and solutions producing perfect population transfer are obtained for up to five-level quantum chains. The Gröbner basis analysis technique is used to generalize the results and get all analytical solutions for perfect population transfer. Explicit formulas for the solutions up to nine levels are presented. These results could be used to design control strategies for general finite-dimensional quantum systems.
MOLECULAR DYNAMICS SIMULATION THE HYDROXYAPATITE SCALE INHIBITION MECHANISM OF WATER-SOLUBLE POLYMERS
Authors: ZHANG SHU-GUANG , WANG FENG-YUN , TAN XIAO-YAO
Published: December 2010

Molecular dynamics (MD) method was used to simulate the interaction between water-soluble polymers, such as polyacrylic acid (PAA), polymethylacrylic acid (PMAA), acrylic acid-methylacrylate copolymer (AA-MAE), acrylic acid-hydroxypropyl acrylate copolymer (AA-HPA), hydrolyzed polymaleic anhydride (HPMA), acrylic acid-maleic acid copolymer (AA-MA), and hydroxyapatite crystal. The sequence of binding energies of polymers binding with the (100) crystal surface of hydroxyapatite was as follows: AA-HPA > AA-MA > HPMA > PAA > AA-MAE > PMAA. After analyzing various energy components and pair correlation functions of all systems, it could be concluded that binding energies were mainly determined by Coulomb interaction. Polymers deformed during their combining with the hydroxyapatite crystal, but all the deformation energies were far less than respective nonbond energies. The dynamics behavior of carboxyls located at different positions of the polymer chains manifested different features during the processes of MD runs. Carboxyls at the ends of the polymer chains oscillated more acutely than those in the middle of the chains; therefore, the latter ones inhibited scale crystal growth more effectively than the former ones because they combined with hydroxyapatite crystal more firmly.
ELECTRONIC STRUCTURES, EXCITED SPECTRA, AND NONLINEAR OPTICAL PROPERTIES OF N-METHYL–FULLEROPYRROLIDINE–OLIGOANILINE DYADS NMPC60–ANn (n = 1–5): QUANTUM CHEMISTRY STUDY
Authors: WANG JIN-YUN , LIN CHEN-SHENG , ZHANG MIN-YI , CHAI GUO-LIANG , ZHANG HAO , HE ZHANG-ZHEN , CHENG WEN-DAN
Published: December 2010

The geometrical and electronic structures of a series of dyads NMPC60–AN n (n = 1–5) were investigated at B3LYP/6-31G* level. Then, the excited states were calculated at TDB3LYP/3-21G* level to investigate the photophysical properties. The third-order polarizabilities of degenerate four-wave mixing (DFWM), electric-field-induced second-harmonic generation (EFISHG), and third-harmonic generation (THG) were calculated in combination with the sum-over-states (SOS) method. The obtained absorption spectra show a remarkable red shift. The average value of third-order polarizabilities 〈γ〉 away from the resonant region increases with n for NMPC60–AN n. The charge transfers from the oligoanilines to C60 cage make the main contribution to the large third-order polarizabilities of this series of compounds. It is found that 〈γ〉 can be expressed as a function of the chain length of linked oligoaniline and 11.74 × 10-34 esu is the upper limit after n = 7 for NMPC60–AN n in the static state.
NBTI-Aware Clustered Power Gating
Authors: Calimera Andrea , Macii Enrico , Poncino Massimo
Published: December 2010

The emergence of Negative Bias Temperature Instability (NBTI) as the most relevant source of reliability in sub-90nm technologies has led to a new facet of the traditional trade-off between power and reliability. NBTI effects in fact manifest themselves as an increase of the propagation delay of the devices over time, which adds up to the delay penalty incurred by most low-power design solutions. This implies that, given a desired lifetime of a circuit (i.e., a given performance target at some point in time), a power-managed component will fail earlier than a nonpower-managed one.

In this work, we show how it is possible to partially overcome this conflict, by leveraging the benefits in terms of aging provided by power-gating (i.e., by using switches that disconnect a logic block from the ground). Thanks to some electrical properties, it is possible to nullify aging effects during standby periods.

Based on this important property, we propose a methodology for a
NBTI-aware
power gating that allows synthesizing low-leakage circuits with maximum lifetime.
Low-Power Hypercube Divided Memory FFT Engine Using 3D Integration
Authors: Thorolfsson Thorlindur , Melamed Samson , Davis W. Rhett , Franzon Paul D.
Published: December 2010

In this article we demonstrate a floating point FFT processor that leverages both 3D integration and a unique hypercube memory division scheme to reduce the power consumption of a 1024 point FFT down to 4.227
μJ
. The hypercube memory division scheme lowers the energy per memory access by 59.2% and increases the total required area by 16.8%. The use of 3D integration reduces the logic power by 5.2%. We describe the tool flow required to realize the 3D implementation and perform a thermal analysis of it.
Energy- and Performance-Efficient Communication Framework for Embedded MPSoCs through Application-Driven Release Consistency
Authors: Yu Chenjie , Petrov Peter
Published: December 2010

We present a framework for performance-, bandwidth-, and energy-efficient intercore communication in embedded MultiProcessor Systems-on-a-Chip (MPSoC). The methodology seamlessly integrates compiler, operating system, and hardware support to achieve a low-cost communication between synchronized producers and consumers. The technique is especially beneficial for data-streaming applications exploiting pipeline parallelism with computational phases mapped to separate cores. Code transformations utilizing a simple ISA support ensure that producer writes are propagated to consumers with a single interconnect transaction per cache block just prior to the producer exiting its synchronization region. Furthermore, in order to completely eliminate misses to shared data caused by interference with private data and also to minimize the cache energy, we integrate to the proposed framework a cache way partitioning policy based on a simple cache configurability support, which isolates the shared buffers from other cache traffic. This mechanism results in significant power savings since only a subset of the cache ways needs to be looked up for each cache access. The end result of the proposed framework is a single communication transaction per shared cache block between a producer and a consumer with no coherence misses on the consumer caches. Our experiments demonstrate significant reductions in interconnect traffic, cache misses, and energy for a set of multiprocessor benchmarks.
A Simultaneous Input Vector Control and Circuit Modification Technique to Reduce Leakage with Zero Delay Penalty
Authors: Jayakumar Nikhil , Khatri Sunil P.
Published: December 2010

Leakage power currently comprises a large fraction of the total power consumption of an IC. Techniques to minimize leakage have been researched widely. However, most approaches to reducing leakage have an associated performance penalty. In this article, we present an approach which minimizes leakage by simultaneously modifying the circuit while deriving the input vector that minimizes leakage. In our approach, we selectively modify a gate so that its output (in sleep mode) is in a state which helps minimize the leakage of other gates in its transitive fanout. Gate replacement is performed in a slack-aware manner, to minimize the resulting delay penalty. One of the major advantages of our technique is that we achieve a significant reduction in leakage without increasing the delay of the circuit.
Application of TLRO to dining philosophers problem
Authors: Bandyopadhyay Anup Kumar , Lenka Nibedita
Published: December 2010

Recently modeling of a state transition rule has been proposed using a temporal logic based on observation (TLRO). Theadvantage of such representation lies in the fact that the model is derived from the related cause and effect relation and is expressed as an implication. This structure makes manipulationeasy. Unlike weakest precondition calculus that can only reason backward in time, present model can include both backward and forward temporal reasoning. This is therefore more expressive. In this paper TLRO based modeling is used to derive three different deadlock free solutions for Dining Philosophers problem. All this solutions are proved using this model
Spatial ordering of messages in a cyclic architecture
Authors: Bandyopadhyay Anup Kumar
Published: December 2010

Spatial ordering of messages can be used fruitfully for the design of distributed systems. For modeling such systems we require a logical framework that includes both spatial andtemporal ordering predicates. In order to illustrate its applicability a distributed K mutual exclusion algorithm is proposed that requires a unidirectional cyclic topology for its implementation. The algorithm uses only point to point communication rather than broadcast. It is shown that the topological ordering of messages is important for its correct operation
People management in software industry
Authors: Mishra Amit , Misra Sanjay
Published: December 2010

Performance differences have been proved among software professionals even in the conditions of identical task. Companies and organizations are aware of the fact that talent has great effect on their success; still most of the software development organizations are focusing so much on tools and technology and little on people. In this paper, we are trying to uncover the relation between the people management-human resource management and software engineering.
Design property metrics to maintainability estimation
Authors: Nair T.R. Gopalakrishnan , Aravindh Sri , Selvarani R.
Published: December 2010

Software maintenance is a vital component that every company has to face when their product is delivered to the stakeholders. This task may span for more than ten years at the customer site.The cost of maintenance or keeping software operational consumes 60-70% of its entire life cycle cost. Definingmaintainability at the design stage of the software development life cycle (SDLC) will result in a cost effective product. In this paper, we proposed a design time relationship model between design properties and the maintainability of the software. This analysis is performed based on the influence of object oriented design metrics on software maintainability
ETDSOA
Authors: Sengupta Abhik , Nandey Vivek , Sengupta Sabnam
Published: December 2010

Service Oriented Architecture (SOA) is the paradigm for IT architecture definition that has been recognized by the industry and analyst groups as a new enterprise architectural technique with the potential to transform businesses into agile enterprises. This paper discusses the emergent variant of Event and Time driven SOA (ETDSOA) and discusses application areas. It proposes a technique for conversion of a traditional and classical SOA viewpoint into one of ETDSOA. The paper provides a model for depicting a representative process flow following the ETDSOA paradigm, using traditional modeling constructs. This can be used gainfully to design solutions following the ETDSOA paradigm with any commonly available standard SOA framework. The inputs can be used as well, for initially implementing the framework with the benefit of improving ETDSOA solution development
Automatic generation of design search keywords from software specifications to improve design search results
Authors: Suri P. K. , Singh Gurdev
Published: December 2010

Software Design Notation Storage and Inference Mechanism (DNSIM) is capable of storing software designs by using Design Markup Language (DGML) tags and reusing existing design elements to produce new software designs. This mechanism performs search operations on stored designs. The accuracy of the search results depends upon the correctness of the keywords provided to the search process. The challenge is to input the Software Requirement Specification (SRS) document as a search input to DNSIM and to produce the best possible design from existing design elements. This paper proposes a method to produce requirement specification keywords from the formal representation of the SRS. The DNSIM system uses the keywords produced by our method and shows significant improvements and accuracy in the design search results
Measuring class cohesion using mutant methods
Authors: Tee Sim-Hui
Published: December 2010

Class cohesion is a measure of software quality and maintainability. A highly cohesive class implies that its modules are functionally coherent and integrated. To date, there are varying cohesion metrics that measure class cohesion from different perspectives. These metrics use different computation in the evaluation of class cohesion. Novice software developers have no access to the class cohesion of a particular class if they are not familiar with these metrics. In this paper, we provide a quick technique to measure class cohesion without using complicated calculation. We delimit our technique to measure class cohesion in term of attribute sharing and method invocation. We contend that the observation of the impact of mutant methods provides a quick judgement on the cohesion status. The proposed approach enables novice software developers to quickly evaluate the cohesion status of a class
Video-based reconstruction of animatable human characters
Authors: Stoll Carsten , Gall Juergen , de Aguiar Edilson , Thrun Sebastian , Theobalt Christian
Published: December 2010

We present a new performance capture approach that incorporates a physically-based cloth model to reconstruct a rigged fully-animatable virtual double of a real person in loose apparel from multi-view video recordings. Our algorithm only requires a minimum of manual interaction. Without the use of optical markers in the scene, our algorithm first reconstructs skeleton motion and detailed time-varying surface geometry of a real person from a reference video sequence. These captured reference performance data are then analyzed to automatically identify non-rigidly deforming pieces of apparel on the animated geometry. For each piece of apparel, parameters of a physically-based real-time cloth simulation model are estimated, and surface geometry of occluded body regions is approximated. The reconstructed character model comprises a skeleton-based representation for the actual body parts and a physically-based simulation model for the apparel. In contrast to previous performance capture methods, we can now also create new real-time animations of actors captured in general apparel.
Circularly polarized spherical illumination reflectometry
Authors: Ghosh Abhijeet , Chen Tongbo , Peers Pieter , Wilson Cyrus A. , Debevec Paul
Published: December 2010

We present a novel method for surface reflectometry from a few observations of a scene under a single uniform spherical field of circularly polarized illumination. The method is based on a novel analysis of the Stokes reflectance field of circularly polarized spherical illumination and yields per-pixel estimates of diffuse albedo, specular albedo, index of refraction, and specular roughness of isotropic BRDFs. To infer these reflectance parameters, we measure the Stokes parameters of the reflected light at each pixel by taking four photographs of the scene, consisting of three photographs with differently oriented linear polarizers in front of the camera, and one additional photograph with a circular polarizer. The method only assumes knowledge of surface orientation, for which we make a few additional photometric measurements. We verify our method with three different lighting setups, ranging from specialized to off-the-shelf hardware, which project either discrete or continuous fields of spherical illumination. Our technique offers several benefits: it estimates a more detailed model of per-pixel surface reflectance parameters than previous work, it requires a relatively small number of measurements, it is applicable to a wide range of material types, and it is completely viewpoint independent.
Combining global and local virtual lights for detailed glossy illumination
Authors: Davidovič Tomáš , Křivánek Jaroslav , Hašan Miloš , Slusallek Philipp , Bala Kavita
Published: December 2010

Accurately rendering glossy materials in design applications, where previewing and interactivity are important, remains a major challenge. While many fast global illumination solutions have been proposed, all of them work under limiting assumptions on the materials and lighting in the scene. In the presence of many glossy (directionally scattering) materials, fast solutions either fail or degenerate to inefficient, brute-force simulations of the underlying light transport. In particular, many-light algorithms are able to provide fast approximations by clamping elements of the light transport matrix, but they eliminate the part of the transport that contributes to accurate glossy appearance. In this paper we introduce a solution that separately solves for the global (low-rank, dense) and local (highrank, sparse) illumination components. For the low-rank component we introduce visibility clustering and approximation, while for the high-rank component we introduce a
local light
technique to correct for the missing illumination. Compared to competing techniques we achieve superior gloss rendering in minutes, making our technique suitable for applications such as industrial design and architecture, where material appearance is critical.
Cone carving for surface reconstruction
Authors: Shalom Shy , Shamir Ariel , Zhang Hao , Cohen-Or Daniel
Published: December 2010

We present cone carving, a novel space carving technique supporting topologically correct surface reconstruction from an incomplete scanned point cloud. The technique utilizes the point samples not only for local surface position estimation but also to obtain global visibility information under the assumption that each acquired point is visible from a point lying outside the shape. This enables associating each point with a generalized cone, called the
visibility cone
, that carves a portion of the outside ambient space of the shape from the inside out. These cones collectively provide a means to better approximate the signed distances to the shape specifically near regions containing large holes in the scan, allowing one to infer the correct surface topology. Combining the new distance measure with conventional RBF, we define an implicit function whose zero level set defines the surface of the shape. We demonstrate the utility of cone carving in coping with significant missing data and raw scans from a commercial 3D scanner as well as synthetic input.
Automatic reconstruction of tree skeletal structures from point clouds
Authors: Livny Yotam , Yan Feilong , Olson Matt , Chen Baoquan , Zhang Hao , El-Sana Jihad
Published: December 2010

Trees, bushes, and other plants are ubiquitous in urban environments, and realistic models of trees can add a great deal of realism to a digital urban scene. There has been much research on
modeling
tree structures, but limited work on
reconstructing
the geometry of real-world trees -- even then, most works have focused on reconstruction from photographs aided by significant user interaction. In this paper, we perform active laser scanning of real-world vegetation and present an automatic approach that robustly reconstructs skeletal structures of trees, from which full geometry can be generated. The core of our method is a series of
global optimizations
that fit skeletal structures to the often sparse, incomplete, and noisy point data. A significant benefit of our approach is its ability to reconstruct multiple overlapping trees simultaneously without segmentation. We demonstrate the effectiveness and robustness of our approach on many raw scans of different tree varieties.
Real-time collision culling of a million bodies on graphics processing units
Authors: Liu Fuchang , Harada Takahiro , Lee Youngeun , Kim Young J.
Published: December 2010

We cull collisions between very large numbers of moving bodies using graphics processing units (GPUs). To perform massively parallel sweep-and-prune (SaP), we mitigate the great density of intervals along the axis of sweep by using principal component analysis to choose the best sweep direction, together with spatial subdivisions to further reduce the number of false positive overlaps. Our algorithm implemented entirely on GPUs using the CUDA framework can handle a million moving objects at interactive rates. As application of our algorithm, we demonstrate the real-time simulation of very large numbers of particles and rigid-body dynamics.
Piles of objects
Authors: Hsu Shu-Wei , Keyser John
Published: December 2010

We present a method for directly modeling piles of objects in multi-body simulations. Piles of objects represent some of the more interesting, but also most time-consuming portion of simulation. We propose a method for reducing computation in many of these situations by explicitly modeling the piles that the objects may form into. By modeling pile behavior rather than the behavior of all individual objects, we can achieve realistic results in less time, and without directly modeling the frictional component that leads to desired pile shapes. Our method is simple to implement and can be easily integrated with existing rigid body simulations. We observe notable speedups in several rigid body examples, and generate a wider variety of piled structures than possible with strict impulse-based simulation.
Animation wrinkling
Authors: Rohmer Damien , Popa Tiberiu , Cani Marie-Paule , Hahmann Stefanie , Sheffer Alla
Published: December 2010

Moving garments and other cloth objects exhibit dynamic, complex wrinkles. Generating such wrinkles in a virtual environment currently requires either a time-consuming manual design process, or a computationally expensive simulation, often combined with accurate parameter-tuning requiring specialized animator skills. Our work presents an alternative approach for wrinkle generation which combines coarse cloth animation with a post-processing step for efficient generation of realistic-looking fine dynamic wrinkles. Our method uses the stretch tensor of the coarse animation output as a guide for wrinkle placement. To ensure temporal coherence, the placement mechanism uses a space-time approach allowing not only for smooth wrinkle appearance and disappearance, but also for wrinkle motion, splitting, and merging over time. Our method generates believable wrinkle geometry using specialized curve-based implicit deformers. The method is fully automatic and has a single user control parameter that enables the user to mimic different fabrics.
Spectral sampling of manifolds
Authors: Öztireli A. Cengiz , Alexa Marc , Gross Markus
Published: December 2010

A central problem in computer graphics is finding optimal sampling conditions for a given surface representation. We propose a new method to solve this problem based on spectral analysis of manifolds which results in faithful reconstructions and high quality isotropic samplings, is efficient, out-of-core, feature sensitive, intuitive to control and simple to implement. We approach the problem in a novel way by utilizing results from spectral analysis, kernel methods, and matrix perturbation theory. Change in a manifold due to a single point is quantified by a local measure that limits the change in the Laplace-Beltrami spectrum of the manifold. Hence, we do not need to explicitly compute the spectrum or any global quantity, which makes our algorithms very efficient. Although our main focus is on sampling surfaces, the analysis and algorithms are general and can be applied for simplifying and resampling point clouds lying near a manifold of arbitrary dimension.
Scalable fluid simulation using anisotropic turbulence particles
Authors: Pfaff Tobias , Thuerey Nils , Cohen Jonathan , Tariq Sarah , Gross Markus
Published: December 2010

It is usually difficult to resolve the fine details of turbulent flows, especially when targeting real-time applications. We present a novel, scalable turbulence method that uses a realistic energy model and an efficient particle representation that allows for the accurate and robust simulation of small-scale detail. We compute transport of turbulent energy using a complete two-equation
k
-ε model with accurate production terms that allows us to capture anisotropic turbulence effects, which integrate smoothly into the base flow. We only require a very low grid resolution to resolve the underlying base flow. As we offload complexity from the fluid solver to the particle system, we can control the detail of the simulation easily by adjusting the number of particles, without changing the large scale behavior. In addition, no computations are wasted on areas that are not visible. We demonstrate that due to the design of our algorithm it is highly suitable for massively parallel architectures, and is able to generate detailed turbulent simulations with millions of particles at high framerates.
Multi-phase fluid simulations using regional level sets
Authors: Kim Byungmoon
Published: December 2010

We address the problem of Multi-Phase (or Many-Phase) Fluid simulations. We propose to use the regional level set (RLS) that can handle a large number of regions and materials, and hence, is appropriate for simulations of many immiscible materials. Towards this goal, we improve the interpolation of the RLS, and develop the regional level set graph (RLSG), which registers connected components and their contacts, and tracks their properties such as region volumes, film life times, and film material types, as regions evolve, merge, split, or are squeezed into films. Using RLSG's tracking feature, we generate particles from tiny regions or rupturing films.
Detail-preserving fully-Eulerian interface tracking framework
Authors: Heo Nambin , Ko Hyeong-Seok
Published: December 2010

This paper introduces a fully-Eulerian interface tracking framework that preserves the fine details of liquids. Unlike existing Eulerian methods, the proposed framework shows good mass conservation even though it does not employ conventional Lagrangian elements. In addition, it handles complex merging and splitting of interfaces robustly due to the implicit representation. To model the interface more accurately, a high order polynomial reconstruction of the signed distance function is utilized based on a number of sub-grid quadrature points. By combining this accurate polynomial representation with a high-order re-initialization method, the proposed framework preserves the detailed structures of the interface. Moreover, the method is simple to implement, unconditionally stable, and is suitable for parallel computing environments.
A hierarchical volumetric shadow algorithm for single scattering
Authors: Baran Ilya , Chen Jiawen , Ragan-Kelley Jonathan , Durand Frédo , Lehtinen Jaakko
Published: December 2010

Volumetric effects such as beams of light through participating media are an important component in the appearance of the natural world. Many such effects can be faithfully modeled by a single scattering medium. In the presence of shadows, rendering these effects can be prohibitively expensive: current algorithms are based on ray marching, i.e., integrating the illumination scattered towards the camera along each view ray, modulated by visibility to the light source at each sample. Visibility must be determined for each sample using shadow rays or shadow-map lookups. We observe that in a suitably chosen coordinate system, the visibility function has a regular structure that we can exploit for significant acceleration compared to brute force sampling. We propose an efficient algorithm based on partial sum trees for computing the scattering integrals in a single-scattering homogeneous medium. On a CPU, we achieve speedups of 17--120x over ray marching.
Volumetric modeling with diffusion surfaces
Authors: Takayama Kenshi , Sorkine Olga , Nealen Andrew , Igarashi Takeo
Published: December 2010

The modeling of volumetric objects is still a difficult problem. Solid texture synthesis methods enable the design of volumes with homogeneous textures, but global features such as smoothly varying colors seen in vegetables and fruits are difficult to model. In this paper, we propose a representation called
diffusion surfaces
(DSs) to enable modeling such objects. DSs consist of 3D surfaces with colors defined on both sides, such that the interior colors in the volume are obtained by diffusing colors from nearby surfaces. A straightforward way to compute color diffusion is to solve a volumetric Poisson equation with the colors of the DSs as boundary conditions, but it requires expensive volumetric meshing which is not appropriate for interactive modeling. We therefore propose to interpolate colors only locally at user-defined cross-sections using a modified version of the positive mean value coordinates algorithm to avoid volumetric meshing. DSs are generally applicable to model many different kinds of objects with internal structures. As a case study, we present a simple sketch-based interface for modeling objects with rotational symmetries that can also generate random variations of models. We demonstrate the effectiveness of our approach through various DSs models with simple non-photorealistic rendering techniques enabled by DSs.