Formal representation of the SS-DB benchmark and experimental evaluation in EXTASCID Evaluating the performance of scientific data processing systems is a difficult task considering the plethora of application-specific solutions available in this landscape and the lack of a generally-accepted benchmark. The dual structure of scientific data coupled with the complex nature of processing complicate the evaluation procedure further. SS-DB is the first attempt to define a general benchmark for complex scientific processing over raw and derived data. It fails to draw sufficient attention though because of the ambiguous plain language specification and the extraordinary SciDB results. In this paper, we remedy the shortcomings of the original SS-DB specification by providing a formal representation in terms of ArrayQL algebra operators and ArrayQL/SciQL constructs. These are the first formal representations of the SS-DB benchmark. Starting from the formal representation, we give a reference implementation and present benchmark results in EXTASCID, a novel system for scientific data processing. EXTASCID is complete in providing native support both for array and relational data and extensible in executing any user code inside the system by the means of a configurable metaoperator. These features result in significant improvement over SciDB at data loading, extracting derived data, and operations over derived data.

O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

array databases
array algebra
array query languages
benchmark evaluation


performance analysis of cooley-tukey fft algorithms for a many-core architecture Given that many-core architectures are becoming the mainstream framework for high performance computing, it is important to develop a performance model for many-core architectures to assist parallel algorithms design and applications performance tuning. In this paper, we propose a performance modeling technique for parallel Cooley-Tukey FFT algorithms, for an abstract many-core architecture that captures generic features and parameters of a class of real many-core architectures. We have verified our performance model on the IBM Cyclops-64 (C64) many-core architecture. The experimental results demonstrate that our model can predict the performance trend accurately, with an average relative error of 16\%, when running on up to 16 cores. The average relative error rate gradually increases to 29\%, when running on up to 64 cores. The experimental results also reveal that key to performance for this class of many-core architectures is using the local memory and higher radix algorithms to reduce the memory traffic requirements.

B I O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Smooth Nonnegative Matrix Factorization for Unsupervised Audiovisual Document Structuring This paper introduces a new paradigm for unsupervised audiovisual document structuring. In this paradigm, a novel Nonnegative Matrix Factorization (NMF) algorithm is applied on histograms of counts (relating to a bag of features representation of the content) to jointly discover latent structuring patterns and their activations in time. Our NMF variant employs the Kullback-Leibler divergence as a cost function and imposes a temporal smoothness constraint to the activations. It is solved by a majorization-minimization technique. The approach proposed is meant to be generic and is particularly well suited to applications where the structuring patterns may overlap in time. As such, it is evaluated on two person-oriented video structuring tasks (one using the visual modality and the second the audio). This is done using a challenging database of political debate videos. Our results outperform reference results obtained by a method using Hidden Markov Models. Further, we show the potential that our general approach has for audio speaker diarization.

O O B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O

bag of features
matrix factorization
videos

content structuring
indexing
machine learning
unsupervised classification


High-performance land surface modeling with a Linux cluster The Land Information System (LIS) was developed at NASA to perform global land surface simulations at a resolution of l-km or finer in real time. Such unprecedented scales and intensity pose many computational challenges. In this article, we demonstrate some of our approaches in high-performance computing with a Linux cluster to meet these challenges and reach our performance goals. These approaches include job partition and a job management system for parallel processing on the cluster, high-performance parallel input/output based on GrADS-DODS (GDS) servers, dynamic load-balancing and distributed data storage techniques, and highly scalable data replication with peer-to-peer (P2P) technology. These techniques work coherently to provide a high-performance land surface modeling system featuring fault tolerance, optimal resource utilization, and high scalability. Examples are given with LIS's high-resolution modeling of surface runoff during 2003 to illustrate LIS's capability to enable new scientific explorations. (C) 2008 Elsevier Ltd. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

hydrology modeling
beowulf cluster
distributed computing
parallel computing
peer-to-peer network
high-resolution simulation


eXamine: Exploring annotated modules in networks Biological networks have a growing importance for the interpretation of high-throughput omics data. Integrative network analysis makes use of statistical and combinatorial methods to extract smaller subnetwork modules, and performs enrichment analysis to annotate the modules with ontology terms or other available knowledge. This process results in an annotated module, which retains the original network structure and includes enrichment information as a set system. A major bottleneck is a lack of tools that allow exploring both network structure of extracted modules and its annotations.

O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

set-based annotation
visualization
cytoscape


Mesh optimization using global error with application to geometry simplification This paper presents a linear running time optimization algorithm for meshes with subdivision connectivity, e.g., subdivision surfaces. The algorithm optimizes a model using a metric defined by the user. Two functionals are used to build the metric: a rate functional and a distortion (i.e. error) functional. The distortion functional defines the error function to minimize, whereas the rate functional defines the minimization constraint. The algorithm computes approximations within this metric using jointly global error and an optimal vertex selection technique inspired from optimal tree pruning algorithms used in compression. We present an update mechanism, that we name merging domain intersections (MDIs), allowing the control of global error through the optimization process at low cost. Our method has application in progressive model decomposition, compression, rendering, and finite element methods. We apply our method to geometry simplification and present an algorithm to compute a decomposition of a model into a multiresolution hierarchy in 0 (n log n) time using global error, where n is the number of vertices in the full-resolution model. We show that a direct approach, i.e. not using MDIs, recomputing global error has at least cost O(n(2)). We analyze the optimality of the algorithm and give several for its properties. We present results for semi-regular meshes obtained from approximation of subdivision surfaces whose connectivity is obtain from (triangulated) quadrilateral quadrisection (e.g. 4-8 or Catmull-Clark subdivision). (C) 2002 Elsevier Science (USA).

B I O B I O O O B I O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O

mesh optimization
global error
subdivision surfaces
geometry simplification


Cooperative reinforcement learning in topology-based multi-agent systems Topology-based multi-agent systems (TMAS), wherein agents interact with one another according to their spatial relationship in a network, are well suited for problems with topological constraints. In a TMAS system, however, each agent may have a different state space, which can be rather large. Consequently, traditional approaches to multi-agent cooperative learning may not be able to scale up with the complexity of the network topology. In this paper, we propose a cooperative learning strategy, under which autonomous agents are assembled in a binary tree formation (BTF). By constraining the interaction between agents, we effectively unify the state space of individual agents and enable policy sharing across agents. Our complexity analysis indicates that multi-agent systems with the BTF have a much smaller state space and a higher level of flexibility, compared with the general form of n-ary (n > 2) tree formation. We have applied the proposed cooperative learning strategy to a class of reinforcement learning agents known as temporal difference-fusion architecture for learning and cognition (TD-FALCON). Comparative experiments based on a generic network routing problem, which is a typical TMAS domain, show that the TD-FALCON BTF teams outperform alternative methods, including TD-FALCON teams in single agent and n-ary tree formation, a Q-learning method based on the table lookup mechanism, as well as a classical linear programming algorithm. Our study further shows that TD-FALCON BTF can adapt and function well under various scales of network complexity and traffic volume in TMAS domains.

O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

cooperative learning
reinforcement learning
binary tree formation
policy sharing


Content-based multiple bitstream image transmission over noisy channels In this paper, we propose a novel combined source and channel coding scheme for image transmission over noisy channels. The main feature of the proposed scheme is a systematic decomposition of image sources so that unequal error protection can be applied according to not only bit error sensitivity but also visual content importance. The wavelet transform is adopted to hierarchically decompose the image. The association between the wavelet coefficients and what they represent spatially in the original image is fully exploited so that wavelet blocks are classified based on their corresponding image content. The classification produces wavelet blocks in each class with similar content and statistics, therefore enables high performance source compression using set partitioning in hierarchical trees (SPIHT) algorithm. To combat the channel noise, an unequal error protection strategy with rate-compatible punctured convolutional/cyclic redundancy check (RCPC/CRC) codes is implemented based on the bit contribution to both peak signal-to-noise ratio (PSNR) and visual quality. At the receiving end, a postprocessing method making use of the SPIHT decoding structure and the classification map is developed to restore the degradation due to the residual error after channel decoding. Experimental results show that the proposed scheme is indeed able to provide protection both for the bits that are more sensitive to errors and for the more important visual content under a noisy transmission environment. In particular, the reconstructed images illustrate consistently better visual quality than using the single-bitstream-based schemes.

O O O O O O B I O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

noisy channels
spiht
unequal error protection

content-based-coding
human visual system
multiple hierarchy
rcpc/crc


Parallel multigrid for anisotropic elliptic equations In this paper two well-known robust multigrid solvers for anisotropic operators on structured grids are compared: alternating-plant: smoothers combined with full coarsening and plane smoothers combined with semi-coarsening. The study has taken into account not only numerical properties but also architectural ones. focusing on cache memory exploitation and parallel characteristics. Experimental results for the sequential algorithms have been obtained on two different systems based on the MIPS R10000 processor. hut with different L2 cache sizes and memory bandwidths (an SGI O2 workstation and an SGI Origin 2000 system). Although the alternating-plane approach is the best choice for sequential implementations. experimental estimations show poor parallel efficiencies. For the semicoarsening alternative two different parallel implementations have been considered. The first one has optimal parallel characteristics bur due to deterioration of the convergence properties its realistic efficiency is not satisfactory. In the second one. some processors remain idle during a short period of time on every multigrid cycle. However. the second parallel algorithm is more efficient since it preserves the numerical properties of the sequential version. Parallel experiments have also been takes on a Gray T3E system. (C) 2001 Academic Press.

B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

anisotropic partial differential equations


Generalized interpolation and its application in super-resolution imaging In this paper, we present a generalized interpolation scheme for image expansion and generation of super-resolution images. This is done by decomposing the image into appropriate subspaces, carrying out interpolation in individual subspaces and subsequently transforming the interpolated values back to the image domain. Various optical and structural properties of the image, such as 3-D shape of an object, regional homogeneity, local variations in scene reflectivity, etc., can be better preserved during the interpolation process. The motivation for doing so has also been explained theoretically. The generalized interpolation scheme is also shown to be useful in perceptually based high-resolution representation of images where interpolation is done on individual groups as per the perceptual necessity. Further, this scheme is also applied to generation of high-resolution transparencies from low resolution transparencies.

O B O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O


the affects of different queuing disciplines over ftp, video and voip performance The objective of the paper is presentation of research the affects of different queuing disciplines on packet delivery for three applications: FTP, Video and VoIP. For modelling, simulation and analysing on these applications is used OPNET (Optimised Network Engineering Tool) environment. In the paper is investigated how the choice of the queuing discipline can affect the applications and utilization of the network resources in the routers.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

tos
fifo queue
weighted-fair queue
priority queue
qos


almost entirely correct mixing with applications to voting In order to design an exceptionally efficient mix network, both asymptotically and in real terms, we develop the notion of almost entirely correct mixing, and propose a new mix network that is almost entirely correct. In our new mix, the real cost of proving correctness is orders of magnitude faster than all other mix nets. The trade-off is that our mix only guarantees "almost entirely correct" mixing, i.e it guarantees that the mix network processed correctly all inputs with high (but not overwhelming) probability. We use a new technique for verifying correctness. This new technique consists of computing the product of a random subset of the inputs to a mix server, then require the mix server to produce a subset of the outputs of equal product. Our new mix net is of particular value for electronic voting, where a guarantee of almost entirely correct mixing may well be sufficient to announce instantly the result of a large election. The correctness of the result can later be verified beyond a doubt using any one of a number of much slower proofs of perfect-correctness, without having to mix the ballots again.

O O O O O B O B O B O B O O O O B O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O B O B O O O O O B O O O O O O O B O O O O O O O O O O B O O O O B O O O O O O O O O B O O O O O O O B O B I O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

network
value
product
applications
order
use
design
correctness
probability
electronic voting
voting
server
cost

efficiency
computation
mix networks
randomization


Compressed Adjacency Matrices: Untangling Gene Regulatory Networks We present a novel technique-Compressed Adjacency Matrices-for visualizing gene regulatory networks. These directed networks have strong structural characteristics: out-degrees with a scale-free distribution, in-degrees bound by a low maximum, and few and small cycles. Standard visualization techniques, such as node-link diagrams and adjacency matrices, are impeded by these network characteristics. The scale-free distribution of out-degrees causes a high number of intersecting edges in node-link diagrams. Adjacency matrices become space-inefficient due to the low in-degrees and the resulting sparse network. Compressed adjacency matrices, however, exploit these structural characteristics. By cutting open and rearranging an adjacency matrix, we achieve a compact and neatly-arranged visualization. Compressed adjacency matrices allow for easy detection of subnetworks with a specific structure, so-called motifs, which provide important knowledge about gene regulatory networks to domain experts. We summarize motifs commonly referred to in the literature, and relate them to network analysis tasks common to the visualization domain. We show that a user can easily find the important motifs in compressed adjacency matrices, and that this is hard in standard adjacency matrix and node-link diagrams. We also demonstrate that interaction techniques for standard adjacency matrices can be used for our compressed variant. These techniques include rearrangement clustering, highlighting, and filtering.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O


software architecture improvement through test-driven development This research involves empirical software engineering studies applied in academic and professional settings to assess the influence of test-driven development on software quality. Particular focus is given to internal software design quality. Pedagogical implications are also examined. Initial results and the study protocol and plans will be presented.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Humanized Mice for the Study of Type 1 Diabetes and Beta Cell Function Our understanding of the basic biology of diabetes has been guided by observations made using animal models, particularly rodents. However, humans are not mice, and outcomes predicted by murine studies are not always representative of actual outcomes in the clinic. In particular, investigators studying diabetes have relied heavily on mouse and rat models of autoimmune type 1-like diabetes, and experimental results using these models have not been representative of many of the clinical trials in type 1 diabetes. In this article, we describe the availability of new models of humanized mice for the study of three areas of diabetes. These include the use of humanized mice for the study of (1) human islet stem and progenitor cells, (2) human islet allograft rejection, and (3) human immunity and autoimmunity. These humanized mouse models provide an important preclinical bridge between in vitro studies and rodent models and the translation of discoveries in these model systems to the clinic.

O O O O O O O O B O B I I O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O

humanized mouse
diabetes
beta cell function


Model-driven monitoring support for the multi-view performance analysis of parallel embedded applications ? This paper describes an approach to carry out performance analysis of parallel embedded applications. The approach is based on measurement, but in addition, the idea of driving the measurement process (application instrumentation and monitoring) by a behavioral model is introduced. Using this model, highly comprehensible performance information can be collected. The whole approach is based on this behavioral model, one instrumentation method and two tools, one for monitoring and the other for visualization and analysis. Each of these is briefly described, and the steps to carry out performance analysis using them are clearly defined. They are explained by means of a case study. Finally, one method to evaluate the intrusiveness of the monitoring approach is proposed, and the intrusiveness results for the case study are presented.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

performance measurement
performance visualization
parallel embedded systems
software instrumentation


ARE THERE NEURAL GENDER DIFFERENCES IN ONLINE TRUST? AN FMRI STUDY ON THE PERCEIVED TRUSTWORTHINESS OF EBAY OFFERS Research provides increasing evidence that women and men differ in their decisions to trust. However, information systems research does not satisfactorily explain why these gender differences exist. One possible reason is that, surprisingly, theoretical concepts often do not address the most obvious factor that influences human behavior: biology. Given the essential role of biological factors-and specifically those of the brain in decisions to trust, the biological influences should naturally include those related to gender. As trust considerations in economic decision making have become increasingly complex with the expansion of Internet use, understanding the related biological/brain functions and the involvement of gender provides a range of valuable insights. To show empirically that online trust is associated with activity changes in certain brain areas, we used functional magnetic resonance imaging (fMRI). In a laboratory experiment, we captured the brain activity of female and 10 male participants simultaneous to decisions on trustworthiness of eBay offers. We found that most of the brain areas that encode trustworthiness differ between women and men. Moreover, we found that women activated more brain areas than did men. These results confirm the empathizing systemizing theory, which predicts gender differences in neural information processing modes. In demonstrating that perceived trustworthiness of Internet offers is affected by neurobiology, our study has major implications for both IS research and management. We confirm the value of a category of research heretofore neglected in IS research and practice, and argue that future IS research investigating human behavior should consider the role of biological 'actors. In practice, biologicalfactors are a significant consideration.for management, marketing, and engineering attempts to influence behavior.

O O O B O O B I O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

online trust
trustworthiness
gender
ebay

functional magnetic resonance imaging (fmri)


Outage capacities and optimal power allocation for fading multiple-access channels We derive the outage capacity region of an M-user fading multiple-access channel (MAC) under the assumption that both the transmitters and the receiver have perfect channel side information (CSI). The outage capacity region is implicitly obtained by deriving the outage probability region for a given rate vector. Given a required rate and average power constraint for each user, we find a successive decoding strategy and a power allocation policy that achieves points on the boundary of the outage probability region. We discuss the scenario where an outage must be declared simultaneously for all users (common outage) and when outages can be declared individually (individual outage) for each user.

O O O B I I O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

capacity region
optimal power allocation
outage probability

fading channels
multiple-access channels (macs)


A hearing-inspired approach for distant-microphone speech recognition in the presence of multiple sources ? This paper addresses the problem of speech recognition in reverberant multisource noise conditions using distant binaural microphones. Our scheme employs a two-stage fragment decoding approach inspired by Bregman's account of auditory scene analysis, in which innate primitive grouping rules are balanced by the role of learnt schema-driven processes. First, the acoustic mixture is split into local time-frequency fragments of individual sound sources using signal-level primitive grouping cues. Second, statistical models are employed to select fragments belonging to the sound source of interest, and the hypothesis-driven stage simultaneously searches for the most probable speech/background segmentation and the corresponding acoustic model state sequence. The paper reports recent advances in combining adaptive noise floor modelling and binaural localisation cues within this framework. By integrating signal-level grouping cues with acoustic models of the target sound source in a probabilistic framework, the system is able to simultaneously separate and recognise the sound of interest from the mixture, and derive significant recognition performance benefits from different grouping cue estimates despite their inherent unreliability in noisy conditions. Finally, the paper will show that missing data imputation can be applied via fragment decoding to allow reconstruction of a clean spectrogram that can be further processed and used as input to conventional ASR systems. The best performing system achieves an average keyword recognition accuracy of 85.83% on the PASCAL CHiME Challenge task.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

auditory scene analysis
binaural localisation

distant-microphone speech recognition
noise robustness


A high dimensional delay selection for the reconstruction of proper phase space with cross auto-correlation For the purpose of phase space reconstruction from nonlinear time series, delay selection is one of the most vital criteria. This is normally done by using a general measure viz., mutual information (MI). However, in that case, the delay selection is limited to the estimation of a single delay using MI between two variables only. The corresponding reconstructed phase space is also not satisfactory. To overcome the situation, a high-dimensional estimator of the MI is used; it selects more than one delay between more than two variables. The quality of the reconstructed phase space is tested by shape distortion parameter (SD), it is found that even this multi-dimensional MI sometimes fails to produce a less distorted phase space. In this paper, an alternative nonlinear measurecross auto-correlation (CAC) is introduced. A comparative study is made between the reconstructed phase spaces of a known three dimensional Neuro-dynamical model, Lorenz dynamical model and a three dimensional food-web model under MI for two and higher dimensions and also under cross auto-correlation separately. It is found that the least distorted phase space is obtained only under the notion of cross auto-correlation.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

dynamical system
phase space reconstructions
cross auto-correlation
shape distortion measure


A COMPARATIVE STUDY OF NEGATIVITY AND CONCURRENCE BASED ON SPIN COHERENT STATES In this paper, we investigate two different entanglement measures, the negativity and concurrence, in the case of pure and mixed states of two-qubit system basing on the spin coherent states. For two-qubit pure states, the negativity is the same as the concurrence. For mixed states, using a simplified expression of concurrence in Wootters' measure of entanglement, we write the bounds of Verstraete et al.(1) as a function of some new parameters and we compare the both measures for a class of mixed states.

O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Partitioning a graph of bounded tree-width to connected subgraphs of almost uniform size Assume that each vertex of a graph G is assigned a nonnegative integer weight and that l and u are nonnegative integers. One wishes to partition G into connected components by deleting edges from G so that the total weight of each component is at least l and at most u . Such an almost uniform partition is called an (l,u) ( l , u ) -partition. We deal with three problems to find an (l,u) ( l , u ) -partition of a given graph; the minimum partition problem is to find an (l,u) ( l , u ) -partition with the minimum number of components; the maximum partition problem is defined analogously; and the p -partition problem is to find an (l,u) ( l , u ) -partition with a fixed number p of components. All these problems are NP-complete or NP-hard, respectively, even for series-parallel graphs. In this paper we show that both the minimum partition problem and the maximum partition problem can be solved in time O(u4n) O ( u 4 n ) and the p -partition problem can be solved in time O(p2u4n) O ( p 2 u 4 n ) for any series-parallel graph with n vertices. The algorithms can be extended for partial k-trees, that is, graphs with bounded tree-width.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

maximum partition problem
minimum partition problem

algorithm
lower bound
(l
u) ( l
u ) -partition (l
u ) (l
u ) ( l
u )
partial k-tree
series-parallel graph
upper bound


a semi-dynamic multiple watermarking schemefor java applications Software protection and security has been a more and more important issue. In order to prevent software from unauthorized use and modification, a great many techniques have been proposed and developed. In this paper, we address this issue through a prevention technique called software watermarking , and we propose a novel software watermarking scheme, which can embed multiple non-interfering watermarks into the same program. Unlike published schemes, this scheme encodes the watermark into mapping functions and then embeds the mapping codes, which are generated from these functions, into the program at the articulation points of its control flow graph. The extraction in this scheme, which is based on dynamically loading a reconstructed program to recover the watermark, is also a novel approach to the software watermarking field. Experimental results indicate that the size and performance overheads caused by this scheme can keep steady.

O O B I O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O

software watermarking
software protection
multiple watermarking

semi-dynamic
software piracy
software security


Balanced bootstrap resampling method for neural model selection Uniform resampling is the easiest to apply and is a general recipe for all problems, but it may require a large replication size B B . To save computational effort in uniform resampling, balanced bootstrap resampling is proposed to change the bootstrap resampling plan. This resampling plan is effective for approximating the center of the bootstrap distribution. Therefore, this paper applies it to neural model selection. Numerical experiments indicate that it is possible to considerably reduce the replication size B B . Moreover, the efficiency of balanced bootstrap resampling is also discussed in this paper.

O B O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O B O O O O O O O O O O O O O B O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O B O O O O O O O

backpropagation multilayer perceptron
balanced resampling


Concurrency control and view notification algorithms for collaborative replicated objects This paper describes algorithms for implementing a high-level programming model for synchronous distributed groupware applications. In this model, several application data objects may be atomically updated, and these objects automatically maintain consistency with their replicas using an optimistic algorithm. changes to these objects may be optimistically or pessimistically observed by view objects by taking consistent snapshots. The algorithms for both update propagation and view notification are based upon optimistic guess propagation principles adapted for fast commit by using primary copy replication techniques. The main contribution of the paper is the synthesis of these two algorithmic techniques-guess propagation and primary copy replication-for implementing a framework that is easy to program to and is well suited for the needs of groupware applications.

O O O O O O O O B I O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O


A linear programming approach to discriminant analysis with a reserved-judgment region A linear-programming model is proposed for deriving discriminant rules that allow allocation of entities to a reserved-judgment region. The size of the reserved-judgment region, which can be controlled by varying parameters within the model, dictates the level of aggressiveness (cautiousness) of allocating (misallocating) entities to groups. Results of simulation experiments for various configurations of normal and contaminated normal three-group populations are reported for a variety of parameter selections. Results of cross-validation experiments using real data sets are also reported. Both the simulation and cross-validation experiments include comparison with other discriminant analysis techniques. The results demonstrate that the proposed model is useful for deriving discriminant rules that reduce the chances of misclassification, while maintaining a reasonable level of correct classification.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

artificial intelligence
statistical analysis


Statistical Modeling of 4D Respiratory Lung Motion Using Diffeomorphic Image Registration Modeling of respiratory motion has become increasingly important in various applications of medical imaging (e. g., radiation therapy of lung cancer). Current modeling approaches are usually confined to intra-patient registration of 3D image data representing the individual patient's anatomy at different breathing phases. We propose an approach to generate a mean motion model of the lung based on thoracic 4D computed tomography (CT) data of different patients to extend the motion modeling capabilities. Our modeling process consists of three steps: an intra-subject registration to generate subject-specific motion models, the generation of an average shape and intensity atlas of the lung as anatomical reference frame, and the registration of the subject-specific motion models to the atlas in order to build a statistical 4D mean motion model (4D-MMM). Furthermore, we present methods to adapt the 4D mean motion model to a patient-specific lung geometry. In all steps, a symmetric diffeomorphic nonlinear intensity-based registration method was employed. The Log-Euclidean framework was used to compute statistics on the diffeomorphic transformations. The presented methods are then used to build a mean motion model of respiratory lung motion using thoracic 4D CT data sets of 17 patients. We evaluate the model by applying it for estimating respiratory motion of ten lung cancer patients. The prediction is evaluated with respect to landmark and tumor motion, and the quantitative analysis results in a mean target registration error (TRE) of 3.3 +/- 1.6 mm if lung dynamics are not impaired by large lung tumors or other lung disorders (e.g., emphysema). With regard to lung tumor motion, we show that prediction accuracy is independent of tumor size and tumor motion amplitude in the considered data set. However, tumors adhering to non-lung structures degrade local lung dynamics significantly and the model-based prediction accuracy is lower in these cases. The statistical respiratory motion model is capable of providing valuable prior knowledge in many fields of applications. We present two examples of possible applications in radiation therapy and image guided diagnosis.

O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O

diffeomorphic registration
statistical atlas generation
4d computed tomography (ct)


Fast vector quantization algorithms based on nearest partition set search A fast search method for vector quantization is proposed in this paper. It makes use of the fact that in the generalized Lloyd algorithm (GLA) a vector in a training sequence is either placed in the same minimum distance partition (MDP) as in the previous iteration or in a partition within a very small subset of partitions. The proposed method searches for the MDP for a training vector only in this subset of partitions plus the single previous MDP. As the size of this subset is much smaller than the total number of codevectors, the search process is speeded up significantly. The creation of the subset is essential, as it has a direct effect on the improvement in computation time of the proposed method. The schemes that create the subset efficiently have been proposed. The proposed method generates a codebook identical to that generated using the GLA. It is simple and requires only minor modification of the GLA and a modest amount of additional memory. The experimental results show that the computation time of codebook training was improved by factors from 6.6 to 50.7 and from 5.8 to 70.4 for two test data sets when codebooks of sizes from N = 16 to 2048 were trained. The proposed method was also combined with an earlier published method to further improve the computation time.

O B I O O O B I I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

nearest partition set
vector quantization

data compression
fast codevector search
hyperspectral imagery


The Voynich manuscript: Evidence of the hoax hypothesis In this article, I analyze the Voynich manuscript, using random walk mapping and token/syllable repetition statistics. The results significantly tighten the boundaries for possible interpretations; they suggest that the text has been generated by a stochastic process rather than by encoding or encryption of language. In particular, the so-called Chinese theory now appears less convincing.

O B I O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O

hoax hypothesis
stochastic process
voynich manuscript


A general-purpose finite-volume advection scheme for continuous and discontinuous fields on unstructured grids We present a new general-purpose advection scheme for unstructured meshes based on the use of a variation of the interface-tracking flux formulation recently put forward by O. Ubbink and R. I. Issa (J. Comput. Phys. 153, 26 (1999)), in combination with an extended version of the flux-limited advection scheme of J. Thuburn (J. Comput. Phys. 123, 74 (1996)), for continuous fields. Thus, along with a high-order mode for continuous fields, the new scheme presented here includes optional integrated interface-tracking modes for discontinuous fields. In all modes, the method is conservative, monotonic, and compatible. It is also highly shape preserving. The scheme works on unstructured meshes composed of any kind of connectivity element, including triangular and quadrilateral elements in two dimensions and tetrahedral and hexahedral elements in three dimensions. The scheme is finite-volume based and is applicable to control-volume finite-element and edge-based node-centered computations. An explicit-implicit extension to the continuous-field scheme is provided only to allow for computations in which the local Courant number exceeds unity. The transition from the explicit mode to the implicit mode is performed locally and in a continuous fashion, providing a smooth hybrid explicit-implicit calculation. Results for a variety of test problems utilizing the continuous and discontinuous advection schemes are presented. (C) 2002 Elsevier Science (USA).

O O O B O O O O O O O B I O O O O O B O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O

advection
unstructured meshes
unstructured grids

reconstruction
interface tracking
volume of fluid
finite-volume method


Logistic ordinal regression for the calibration of oscillometric blood pressure monitors A HammersteinWindkessel model to represent the central blood pressure system. A Kalman filter estimated the time varying Fourier series representing the Windkessel model's output signal. The Fourier coefficients of this modeled oscillometry is then used in a next step to drive a logistic regression analysis. A logistic regression analysis based on the signal features of the oscillometry can detect hyper- and hypotension and correct the blood pressures accordingly.

O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O B I O O O O O O O O O O O O O O O O O O O O

blood pressure measurement
oscillometric signal
pulse-pressure signals
bio-signal processing
heart frequency estimation


revisiting a limit on efficient quantum computation In this paper, we offer an exposition of a theorem originally due to Adleman, Demarrais and Huang that shows that the quantum complexity class BQP (Bounded-error Quantum Polynomial time) is contained in the classical counting class PP (Probabilistic Polynomial time). Our proof follows the one given by Fortnow and Rogers that relates quantum computing to counting complexity classes by way of GapP functions. The contribution of this paper is an exposition of an important result that assumes a minimal background in computational complexity theory and no knowledge of quantum mechanics.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O

quantum computing
computational complexity


A bi-objective stochastic optimization model for reliable warehouse network redesign This paper proposes a developed bi-objective two-stage stochastic mixed-integer linear programming model for redesigning a reliable warehouse network. In this model, the warehouses capacity which should be phased out, remained, or relocated to other warehouses, and the shipment quantity of the product between the network nodes with a consideration for two delivery lead times is to be determined. Unlike most previous works, considering two delivery lead times, the maximum capacity for each warehouse location, reliability and uncertainty are taken into account in this study. The proposed bi-objective model includes: (1) minimizing average costs including the sum of fixed, production, transportation, relocation and capacity extension costs; (2) maximizing the coverage percentage of customer demand delivered within the preferred delivery lead time. In order to obtain Pareto optimal solutions, a novel version of epsilon-constraint method (i.e., the augmented epsilon-constraint) is applied. A real industrial case is applied to validate and verify the developed warehouse redesigning network model under reliability concept. (C) 2013 Elsevier Ltd. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

supply chain network redesign
two-stage stochastic programming
bi-objective optimization
augmented epsilon-constraint method


Inter-domain policy violations in multi-hop overlay routes: Analysis and mitigation The Internet is a complex structure arising from the interconnection of numerous autonomous systems (AS), each exercising its own administrative policies to reflect the commercial agreements behind the interconnection. However, routing in service overlay networks is quite capable of violating these policies to its advantage. To prevent these violations, we see an impending drive in the current Internet to detect and filter overlay traffic. In this paper, we first present results from a case study overlay network, constructed on top of PlanetLab, that helps us gain insights into the frequency and characteristics of the different inter-domain policy violations. Further, we investigate the impact of two types of overlay traffic filtering that aim to prevent these routing policy violations: blind filtering and policy-aware filtering. We show that such filtering can be detrimental to the performance of overlay routing. We next consider two approaches that allow the overlay network to realize the full advantage of overlay routing in this context. In the first approach, overlay nodes are added so that good overlay paths do not represent inter-domain policy violations. In the second approach, the overlay acquires permits from certain ASes that allow certain policy violations to occur. We develop a single cost-sharing framework that allows the incorporation of both approaches into a single strategy. We formulate and solve an optimization problem that aims to determine how the overlay network should allocate a given budget between paying for additional overlay nodes and paying for permits (transit and exit) to ASes. We illustrate the use of this approach on our case study overlay network and evaluate its performance under varying network characteristics. (C) 2008 Elsevier B.V. All rights reserved.

O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

inter-domain policies
cross-layer conflict
isp filtering


Existence and uniqueness of a fuzzy solution for the nonlinear fuzzy neutral functional differential equation This work is concerned with a class of nonlinear fuzzy neutral functional differential equations. Specifically, existence and uniqueness of fuzzy solutions for the nonlinear fuzzy neutral functional differential equation d/dt[x(t) - f(t, x(t))] = Ax(t) + g(t, x(t)), where A is a fuzzy coefficient and f and g are continuous functions, axe established via Banach fixed-point analysis approach and using the fuzzy number whose values are normal, convex upper semicontinuous, and compactly supported interval in E-N. (C) 2001 Elsevier Science Ltd. All rights reserved.

O O O O O B I O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O


Optimised robot-based system for the exploration of elastic joint properties Numerous publications provide measured biomechanical data relating to synovial joints. However, in general, they do not reflect the non-linear elastic joint properties in detail or do not consider all degrees of freedom (DOF), or the quantity of data is sparse. To perform more comprehensive, extended measurements of elastic joint properties, an optimised robot-based approach was developed. The basis was an industrial, high-precision robot that was capable of applying loads to the joint and measuring the joint displacement in 6 DOE The system was equipped with novel, custom-made control hardware. In contrast to the commonly used sampling rates that are below 100 Hz, a rate of 4 kHz was realised for each DOF. This made it possible to implement advanced, highly dynamic, quasi-continuous closed-loop controllers. Thus oscillations of the robot were avoided, and measurements were speeded up. The stiffness of the entire system was greater than 44 kNm(-1) and 22 Nm deg(-1), and the maximum difference between two successive measurements was less than 0.5 deg. A sophisticated CT-based referencing routine facilitated the matching of kinematic data with the individual anatomy of the tested joint. The detailed detection of the elastic varus-valgus properties of a human knee joint is described, and the need for high spatial resolution is demonstrated.

O O O O O O O B I I O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

biomechanics
knee kinematics
robotics
joint stiffness


Personalised indexing and retrieval of heterogeneous structured documents In this paper the problem of indexing heterogeneous structured documents and of retrieving semi-structured documents is considered. We propose a flexible paradigm for both indexing such documents and formulating user queries specifying soft constraints on both documents' structure and content. At the indexing level we propose a model that achieves flexibility by constructing personalised document representations based on users' views of the documents. This is obtained by allowing users to specify their preferences on the documents' sections that they estimate to bear the most interesting information, as well as to linguistically quantify the number of sections which determine the global potential interest of the documents. At the query language level, a flexible query language for expressing soft selection conditions on both the documents' structure and content is proposed.

O O O O O B I I O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

content-based and structure-based querying


teaching design patterns using a family of games Object-oriented software design requires a combination of abilities that can not be easily transferred to the students in lecture sessions. Based on our experience, this paper details how to increase student comprehension of design patterns through a project-based approach that consists in the development of a family of abstract strategy games in an incremental way. In this approach, the application resulting from the previous assignment is refined using refactoring and design patterns to complete the next assignment. Our approach is illustrated by the development of a family of n-in-a-row games in a CS3 course.

O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O B O B I O O O O O O O O O O O O O O O O O O O O O O

refactoring
abstract strategy games
design patterns


25-years of data envelopment analysis This retrospective by an early DEA researcher recalls the people, the setting, the formative philosophies, and early implementation experiences with Data Envelopment Analysis. It is a tribute to the founders of DEA, a historical chronicle, and a perspective on the nature and value of this important operations research methodology.

O O B I I O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O

history of operations research
business research methods


Using multirail networks in high-performance clusters Using multiple independent networks (also known as rails) is an emerging technique which is being used to overcome bandwidth limitations and enhance fault tolerance of current high-performance parallel computers. In this paper, we present and analyze various algorithms to allocate multiple communication rails, including static and dynamic allocation schemes. An analytical lower bound on the number of rails required for static rail allocation is shown. We also present an extensive experimental comparison of the behavior of various algorithms in terms of bandwidth and latency. We show that striping messages over multiple rails can substantially reduce network latency, depending on average message size, network load and allocation scheme. The methods compared include a static rail allocation, a basic round-robin rail allocation, a local-dynamic allocation based on local knowledge and a dynamic rail allocation that reserves both communication endpoints of a message before sending it. The last method is shown to perform better than the others at higher loads: up to 49% better than local-knowledge allocation and 37% better than the round-robin allocation. This allocation scheme also shows lower latency and it saturates at higher loads (for long enough messages). Most importantly, this proposed allocation scheme scales well with the number of rails and message size. In addition we propose a hybrid algorithm that combines the benefits of the local- dynamic allocation for short messages with those of the dynamic algorithm for large messages. Copyright (C) 2003 John Wiley Sons, Ltd.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


modeling multi-step relevance propagation for expert finding An expert finding system allows a user to type a simple text query and retrieve names and contact information of individuals that possess the expertise expressed in the query. This paper proposes a novel approach to expert finding in large enterprises or intranets by modeling candidate experts (persons), web documents and various relations among them with so-called expertise graphs. As distinct from the state of-the-art approaches estimating personal expertise through one-step propagation of relevance probability from documents to the related candidates, our methods are based on the principle of multi-step relevance propagation in topic specific expertise graphs. We model the process of expert finding by probabilistic random walks of three kinds: finite, infinite and absorbing. Experiments on TREC Enterprise Track data originating from two large organizations show that our methods using multi-step relevance propagation improve over the baseline one-step propagation based method in almost all cases.

O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O B I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

markov processes
language models
enterprise search


A cybernetic re-evaluation of socio-economic development programs Purpose - To explore the usefulness of the cybernetic approach to support development programs by offering a theoretical framework that helps us to re-understand development and measuring systems. Design/methodology/approach - The paper presents a summary of Beer's theory for organisational development and measuring systems, shows examples of application in design and implementation of socio-economic development programs in Colombia, and uses them to explore the usefulness of the approach in this field. Findings - Analysis of the reported examples shows a clear indication of the usefulness of Beer's approach to design and measure development programs. It reveals an important field for applied research that could benefit from further applications of the approach. Research limitations/implications - The experiences analysed here showed the strength or alliances between government, universities and development agencies, for applied research. It makes clear that more long-term oriented projects are required to fully implement innovative approaches like the one described. Practical implications - Applying a cybernetic approach in this field implies changing from top-down to bottom-up design; wider involvement of stakeholders to agree on critical measurements; changes from emphasis in technological and managerial improvements, to improvements in learning and self-control tools for the developing communities. Originality/value - Even if there has been agreement on the convenience of experimenting with more holistic approaches to socio-economic development, few researchers show the potential of the cybernetic approach, as this paper does.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

cybernetics
organizational development
sociocybernetics
economic development
measurement


Entropy-Functional-Based Online Adaptive Decision Fusion Framework With Application to Wildfire Detection in Video In this paper, an entropy-functional-based online adaptive decision fusion (EADF) framework is developed for image analysis and computer vision applications. In this framework, it is assumed that the compound algorithm consists of several subalgorithms, each of which yields its own decision as a real number centered around zero, representing the confidence level of that particular subalgorithm. Decision values are linearly combined with weights that are updated online according to an active fusion method based on performing entropic projections onto convex sets describing subalgorithms. It is assumed that there is an oracle, who is usually a human operator, providing feedback to the decision fusion method. A video-based wildfire detection system was developed to evaluate the performance of the decision fusion algorithm. In this case, image data arrive sequentially, and the oracle is the security guard of the forest lookout tower, verifying the decision of the combined algorithm. The simulation results are presented.

O O O B I O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

decision fusion
projections onto convex sets

active learning
entropy maximization
online learning
wildfire detection using video


Theoretical design and screening of panchromatic phthalocyanine sensitizers derived from TT1 for dye-sensitized solar cells Computational screening of new dyes is becoming an extremely powerful tool, especially when associated with experimental synthetic efforts that might eventually lead to new and more efficient products. Nine novel unsymmetrical zinc phthalocyanine complexes derived from TT1 were designed as sensitizer candidates for dye-sensitized solar cells with three peripheral CH3, OH, OCH3, OPh, NH2, NHCH3, N(CH3)2, NHPh and N(Ph)2 substituents as the donors and a carboxyl group as the acceptor. The molecular orbital and the electronic absorption spectra properties of these compounds were studied and compared to those of TT1 using the density functional theory and time-dependent density functional theory calculations at B3LYP level with the LANL2DZ basis set. The novel candidates bearing the NH2, NHCH3, N(CH3)2, NHPh and N(Ph)2 moieties as the donors were found to be very promising for providing higher efficiencies than that of TT1 or even the current 4.6% efficiency record held by PcS6. They have higher LUMO levels, smaller energy gaps and red-shifted absorption bands compared to those of TT1. The new absorption bands emerging in 450600nm regions may promote ZnPcL NH2, ZnPcL NHCH3, ZnPcL N(CH3)2, ZnPcL NHPh and ZnPcL N(Ph)2 from near infrared to panchromatic sensitizers. Further experimental synthetic efforts are in progress in our group to validate the predictions in this report.

O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

electronic absorption spectra
phthalocyanine

dye-sensitized solar cells
dft calculations
molecule design
orbital energy level


On privacy and partition arguments A function and f(x(1), x(2),..., x(n)) is said to be t-private if there exists a(randomized)communication protocol for computing f, such that no coalition of at most t participants can infer any additional information from the execution of the protocol other than what follows from their inputs and the value of f. It is known that every n-argument function f defined over finite domains can be computed [n-1/2]-privately. The classes of 1-private two-argument functions and of t-private Boolean functions admit relatively simple characterizations. In contrast, the general question of characterizing the class of t-private functions of n arguments is still open. The only technique that appears in the literature for proving non-t-privacy of a function f(x(1), x(2),.... x(n)) over a finite domain, where n greater than or equal to 3 and [n/2] less than or equal to t less than or equal to n - 1, uses a reduction to the two-party case via a partition argument. A necessary condition for f being t-private is that for every partition (S: (S) over bar) of the parties (1, 2,..., n) such that both \S\ less than or equal to t and \(S) over bar\ less than or equal to t, the two-argument function obtained by viewing f as a function of {x(i)}(i epsilons) and {x(i)}(i epsilon(S) over bar) is 1-private. The question whether the use of such partition reductions together with the two-party characterization is powerful enough to characterize privacy in the multiparty case was raised as an open problem in previous works. These works also exhibit an affirmative answer for specific classes of functions. We answer this question negatively. We show that even if more general partition reductions are used, in which the n parties are partitioned into k sets (2 less than or equal to k less than or equal to n - 1) rather than just two, those reductions are still too weak to characterize privacy. On the other hand, we show that increasing the number of sets k does give some extra characterization power. (C) 2001 Academic Press.

O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Real-time vision and speech driven avatars for multimedia applications Recent progress in advanced video communication services and multimedia applications is grounded on novel human machine interfaces, improved usability, and user friendliness driven by user centric research and development. In this paper, we describe a complete system concept and algorithmic details of an example application within this area. The key features of the system are vision and speech based interfaces, which are used to animate an avatar for an audio-visual representation of a communication partner. The system is applied in two application scenarios, namely video chat and customer care services. Both applications are mass-market oriented and therefore careful design and development of robust and supporting user interfaces are required. The presented approach is integrated into a complete real-time prototype system, which is permanently demonstrated in the showcase at the head quarter of Deutsche Telekom, Bonn, Germany.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

multimodality
real-time tracking
segmentation


PropeR: a multi disciplinary EPR system This article describes the architecture of an EPR system developed for the PropeR project. This EPR system not only aims at supporting home care of stroke patients, but is also designed in such a way that it can be ported to other medical services without much effort. We will briefly describe the Stroke Service and the related PropeR project. Starting from a list of requirements to construct a generic EPR system we will outline the architecture and describe the standards and methods used. Subsequently we describe the implementation and the problems encountered. In the discussion, we will go into the advantages and disadvantages of the tools and techniques we have used.

O O O O B O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

omg hdtf
archetypes
extreme programming
open source
openemed


Multivariate FayHerriot models for small area estimation Multivariate FayHerriot models for estimating small area indicators are introduced. Among the available procedures for fitting linear mixed models, the residual maximum likelihood (REML) is employed. The empirical best predictor (EBLUP) of the vector of area means is derived. An approximation to the matrix of mean squared crossed prediction errors (MSE) is given and four MSE estimators are proposed. The first MSE estimator is a plug-in version of the MSE approximation. The remaining MSE estimators combine parametric bootstrap with the analytic terms of the MSE approximation. Several simulation experiments are performed in order to assess the behavior of the multivariate EBLUP and for comparing the MSE estimators. The developed methodology and software are applied to data from the 2005 and 2006 Spanish living condition surveys. The target of the application is the estimation of poverty proportions and gaps at province level.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O

multivariate linear mixed models
fayherriot model
reml method
mse estimation


A two-level scheduling method: an effective parallelizing technique for uniform nested loops on a DSP multiprocessor A digital signal processor (DSP), which is a special-purpose microprocessor, is designed to achieve higher performance on DSP applications. Because most DSP applications contain many nested loops and permit a very high degree of parallelism, the DSP multiprocessor has a suitable architecture to execute these applications. Unfortunately, conventional scheduling methods used on DSP multiprocessors allocate only one operation to each DSP every time unit, even if the DSP includes several function units that can operate in parallel. Obviously they cannot achieve full function unit utilization. Hence, in this paper, we propose a two-level scheduling method (TSM) to overcome this common failing. TSM contains two approaches, which integrates unimodular transformations, loop tiling technique, and conventional methods used on single DSP. Besides introducing algorithm, we also use an analytic module to analyze its preliminary performance. Based on our analyses the TSM can achieve shorter execution time and more scalable speedup results. In addition, the TSM causes less memory access and synchronization overheads, which are usually negligible in the DSP multiprocessor architecture.

O O B O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O


ORTHOPHOTO FEATURE EXTRACTION AND CLUSTERING In this article we use a combination of neural networks with other techniques for the analysis of orthophotos. Our goal is to obtain results that can serve as a useful groundwork for interactive exploration of the terrain in detail. In our approach we split an aerial photo into a regular grid of segments and for each segment we detect a set of features. These features depict the segment from the viewpoint of a general image analysis (color, tint, etc.) as well as from the viewpoint of the shapes in the segment. We perform clustering based on the Formal Concept Analysis (FCA) and Non-negative Matrix Factorization (NMF) methods and project the results using effective visualization techniques back to the aerial photo. The FCA as a tool allows users to be involved in the exploration of particular clusters by navigation in the space of clusters. In this article we also present two of our own computer systems that support the process of the validation of extracted features using a neural network and also the process of navigation in clusters. Despite the fact that in our approach we use only general properties of images, the results of our experiments demonstrate the usefulness of our approach and the potential for further development.

O O O O B O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

orthophotos
image analysis
neural network
clustering


An analytical performance model for the Spidergon NoC with virtual channels The Spidergon Network-on-Chip (NoC) was proposed to address the demand for a fixed and optimized communication infrastructure for cost-effective multi-processor Systems-on-Chip (MPSoC) development. To deal with the increasing diversity in quality of service requirements of SoC applications, the performance of this architecture needs to be improved. Virtual channels have traditionally been employed to enhance the performance of the interconnect networks. In this paper, we present analytical models to evaluate the message latency and network throughput in the Spidergon NoC and investigate the effect of employing virtual channels. Results obtained through simulation experiments show that the model exhibits a good degree of accuracy in predicting average message latency under various working conditions. Moreover an FPGA implementation of the Spidergon has been developed to provide an accurate analysis of the cost of employing virtual channels in this architecture.

O O O O O O B O O B I O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O B I O O O


Plastic hinge length of circular reinforced concrete columns This paper presents a parametric study of the plastic hinge length of circular reinforced concrete columns using a three-dimensional finite element analysis method, and using the Taguchi robust design method to reduce computational cost. Parameters examined include the longitudinal reinforcing ratio, the shear span-to-depth ratio, the axial force ratio and the concrete compressive strength. The study considers longitudinal reinforcement with yield strengths of 414 MPa and 685 MPa, and proposes simplified formulas for the plastic hinge length of circular reinforced concrete columns, showing that increases in plastic hinge length correlate to increases in the axial load, longitudinal reinforcing and shear span-to-depth ratios. As concrete strength increases, the plastic hinge length decreases for the 414 MPa case but increases for the 685 MPa case.

B I I O O B I I O O O O O O O O B I I O O B I I O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O B I I O O O O B I I O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O

reinforced concrete columns
plastic hinge length
finite element analysis


A modular network scheme for unsupervised 3D object recognition This paper presents an unsupervised learning scheme for recognizing 3D objects from their 2D projected images. The scheme consists of a mixture of nonlinear autoencoders which can compress various views of 3D objects into representations that indicate the view direction. We evaluate the performance of the proposed modular network scheme through simulations using 3D wire-frame objects and discuss its related issues on object representations in the primate visual cortex.

O O O O O O B I I O O O O B I O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

unsupervised learning
3d object recognition
autoencoders


Analysis of co-articulation regions for performance-driven facial animation A facial gesture analysis procedure is presented for the control of animated faces. Facial images are partitioned into a set of local, independently actuated regions of appearance change termed co-articulation regions (CRs). Each CR is parameterized by the activation level of a set of face gestures that affect the region. The activation of a CR is analyzed using independent component analysis (ICA) on a set of training images acquired from an actor. Gesture intensity classification is performed in ICA space by correlation to training samples. Correlation in ICA space proves to be an efficient and stable method for gesture intensity classification with limited training data. A discrete sample-based synthesis method is also presented. An artist creates an actor-independent reconstruction sample database that is indexed with CR state information analyzed in real time from video. Copyright (C) 2004 John Wiley Sons, Ltd.

O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

independent component analysis
animation

facial analysis
performance-driven facial
action units
animation control


Aircraft morphing wing design by using partial topology optimization A morphing wing concept has been investigated over the last decade because it can effectively enhance aircraft aerodynamic performance over a wider range of flight conditions through structural flexibility. The internal structural layouts and component sizes of a morphing aircraft wing have an impact on aircraft performance i.e. aeroelastic characteristics, mechanical behaviors, and mass. In this paper, a novel design approach is proposed for synthesizing the internal structural layout of a morphing wing. The new internal structures are achieved by using two new design strategies. The first design strategy applies design variables for simultaneous partial topology and sizing optimization while the second design strategy includes nodal positions as design variables. Both strategies are based on a ground structure approach. A multiobjective optimization problem is assigned to optimize the percentage of change in lift effectiveness, buckling factor, and mass of a structure subject to design constraints including divergence and flutter speeds, buckling factors, and stresses. The design problem is solved by using multiobjective population-based incremental learning (MOPBIL). The Pareto optimum results of both strategies lead to different unconventional wing structures which are superior to their conventional counterparts. From the results, the design strategy that uses simultaneous partial topology, sizing, and shape optimization is superior to the others based on a hypervolume indicator. The aeroelastic parameters of the obtained morphing wing subject to external actuating torques are analyzed and it is shown that it is practicable to apply the unconventional wing structures for an aircraft.

B I I O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

aircraft morphing wing
multiobjective optimization
topology optimization

aeroelastic design
internal wing structure


Dynamic stiffness matrix of an axisymmetric shell and response to harmonic distributed loads This paper describes a procedure for taking into account distributed loads in the dynamic stiffness matrix formulation, also known as the continuous element method. In that formulation, concentrated or linearly distributed loads are taken into account by considering the necessary number of elements in such a way that these loads are applied on element boundaries. As for distributed loads such as pressure and surface forces, they were not provided for in the formulation. The validation is achieved by comparison of accuracy and computational time of harmonic response calculations performed by the continuous element model and a finite element model.

B I I O O B I O O O O B I O O O O O O O O O B I O O B I I O O O O O B I O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O B I O O O O O O

dynamic stiffness matrix
continuous element
distributed loads
harmonic response
axisymmetric shell


A simple and accurate method for computer-aided transapical aortic valve replacement Transapical aortic valve replacement (TAVR) is a recent minimally invasive surgical treatment technique for elderly and high-risk patients with severe aortic stenosis. In this paper, a simple and accurate image-based method is introduced to aid the intra-operative guidance of TAVR procedure under 2-D X-ray fluoroscopy. The proposed method fuses a 3-D aortic mesh model and anatomical valve landmarks with live 2-D fluoroscopic images. The 3-D aortic mesh model and landmarks are reconstructed from interventional X-ray C-arm CT system, and a target area for valve implantation is automatically estimated using these aortic mesh models. Based on template-based tracking approach, the overlay of visualized 3-D aortic mesh model, landmarks and target area of implantation is updated onto fluoroscopic images by approximating the aortic root motion from a pigtail catheter motion without contrast agent. Also, a rigid intensity-based registration algorithm is used to track continuously the aortic root motion in the presence of contrast agent. Furthermore, a sensorless tracking of the aortic valve prosthesis is provided to guide the physician to perform the appropriate placement of prosthesis into the estimated target area of implantation. Retrospective experiments were carried out on fifteen patient datasets from the clinical routine of the TAVR. The maximum displacement errors were less than 2.0mm for both the dynamic overlay of aortic mesh models and image-based tracking of the prosthesis, and within the clinically accepted ranges. Moreover, high success rates of the proposed method were obtained above 91.0% for all tested patient datasets. The results showed that the proposed method for computer-aided TAVR is potentially a helpful tool for physicians by automatically defining the accurate placement position of the prosthesis during the surgical procedure.

O O O O O O O O B I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

biomedical image processing
computer-aided surgery
image-guided intervention
minimally invasive cardiac surgery
x-ray fluoroscopy


Inference in HIV dynamics models via hierarchical likelihood HIV dynamical models are often based on non-linear systems of ordinary differential equations (ODE), which do not have an analytical solution. Introducing random effects in such models leads to very challenging non-linear mixed-effects models. To avoid the numerical computation of multiple integrals involved in the likelihood, a hierarchical likelihood (h-likelihood) approach, treated in the spirit of a penalized likelihood is proposed. The asymptotic distribution of the maximum h-likelihood estimators (MHLE) for fixed effects is given. The MHLE are slightly biased but the bias can be made negligible by using a parametric bootstrap procedure. An efficient algorithm for maximizing the h-likelihood is proposed. A simulation study, based on a classical HIV dynamical model, confirms the good properties of the MHLE. The method is applied to the analysis of a clinical trial.

O O B I I O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

algorithm
asymptotic
differential equations
hiv dynamics models
penalized likelihood

h-likelihood
non-linear mixed effects model


The open family of temporal logics: Annotating temporal operators with input constraints Assume-guarantee style verification of modules relies on the appropriate modeling of the interaction of the module with its environment. Popular temporal logics such as Computation Tree Logic (CTL) and Linear Temporal Logic (LTL) that were originally defined for closed systems (Kripke structures) do not make any syntactic discrimination between input and output variables. As a result, these logics and their recent derivatives (such as System Verilog, Sugar, Forspec, etc) permit the specification of properties that have some semantic problems when interpreted over open systems or modules. These semantic problems are quite common in practice, but are computationally hard to detect within a given specification. In this article, we propose a new style for writing temporal specifications of open systems that helps the designer to avoid most of these problems. In the proposed style, the basic temporal operators (such as next and until) are annotated with assume constraints over the input variables. We formalize this style through an extension of LTL, namely Open-LTL and an extension of CTL with fairness, called Open-CTL. We show that this simple syntactic separation between the assume and the guarantee achieves the desired results. We show that the proposed style can be integrated with traditional symbolic model-checking techniques and present a complete tool for the verification of Verilog RTL modules in isolation.

O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O


Seismic response analysis models of an oil storage tank with a floating roof Purpose - The purpose of this paper is to investigate the effects of the finite element models on the response of a free surface or a floating roof, which is important for safety assessment of oil storage tanks. Design/methodology/approach - Structural analyses of shell structures using the three-dimensional finite element method (FEM), potential flow analyses by FEM, and fluid-structure interaction analyses by strong coupling of the structural and fluid analyses were performed. In-house software was utilized for computations shown in this paper except the solver for non-symmetric sparse matrix. Findings - A model with a rigid tank and an elastic roof was confirmed to be able to perform the seismic response analysis most effectively from the viewpoint of computational cost with no reduction in accuracy. Research limitations/implications - The stress distribution on the floating roof will be evaluated to assess the safety of oil storage tanks subjected to seismic waves in the future research. Originality/value - This paper shows the dynamic responses of a liquid storage tank subjected to seismic motion using four different analysis models and the results were compared. It was concluded that a model with a rigid tank and an elastic roof can perform the seismic response analysis most effectively from the viewpoint of both accuracy and computational cost.

O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

oils
finite element analysis
potential theory
fluid-structure interaction


Collecting feedback during software engineering experiments Objective: To improve the qualitative data obtained from software engineering experiments by gathering feedback during experiments. Rationale: Existing techniques for collecting quantitative and qualitative data from software engineering experiments do not provide Sufficient information to validate or explain all our results. Therefore, we would like a cost-effective and unobtrusive method of collecting feedback from subjects during an experiment to augment other sources of data. Design of study: We formulated a set of qualitative questions that might be answered by collecting feedback during software engineering experiments. We then developed a tool to collect such feedback from experimental subjects. This feedback-collection tool was used in four different experiments and we evaluated the usefulness of the feedback obtained in the context of each experiment. The feedback data was triangulated with other Sources of quantitative and qualitative data collected for the experiments. Results: We have demonstrated that the collection of feedback during experiments provides useful additional data to: validate the data obtained from other sources about solution times and quality of solutions; check process conformance; understand problem solving processes; identify problems with experiments; and understand subjects' perception of experiments. Conclusions: Feedback collection has proved useful in four experiments and we intend to use the feedback-collection tool in a range of other experiments to further explore the cost-effectiveness and limitations of this technique. It is also necessary to carry out a systematic study to more fully understand the impact of the feedback-collecting tool on subjects' performance in experiments.

O B O B I I O O O O O O O O B I I O O B O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B I I O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

software engineering experiments
feedback

qualitative studies
data collection
tool support
experience sampling


a comparison of retrieval-based hierarchical clustering approaches to person name disambiguation This paper describes a simple clustering approach to person name disambiguation of retrieved documents. The methods are based on standard IR concepts and do not require any task-specific features. We compare different term-weighting and indexing methods and evaluate their performance against the Web People Search task (WePS). Despite their simplicity these approaches achieve very competitive performance.

O O O O O B O O B I I O O O O O B O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O