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141.
ProbExplorer: Uncertainty‐guided Exploration and Editing of Probabilistic Medical Image Segmentation
In this paper, we develop an interactive analysis and visualization tool for probabilistic segmentation results in medical imaging. We provide a systematic approach to analyze, interact and highlight regions of segmentation uncertainty. We introduce a set of visual analysis widgets integrating different approaches to analyze multivariate probabilistic field data with direct volume rendering. We demonstrate the user's ability to identify suspicious regions (e.g. tumors) and correct the misclassification results using a novel uncertainty‐based segmentation editing technique. We evaluate our system and demonstrate its usefulness in the context of static and time‐varying medical imaging datasets. 相似文献
142.
Pradeep K. Atrey M. Anwar Hossain Abdulmotaleb El Saddik Mohan S. Kankanhalli 《Multimedia Systems》2010,16(6):345-379
This survey aims at providing multimedia researchers with a state-of-the-art overview of fusion strategies, which are used
for combining multiple modalities in order to accomplish various multimedia analysis tasks. The existing literature on multimodal
fusion research is presented through several classifications based on the fusion methodology and the level of fusion (feature,
decision, and hybrid). The fusion methods are described from the perspective of the basic concept, advantages, weaknesses,
and their usage in various analysis tasks as reported in the literature. Moreover, several distinctive issues that influence
a multimodal fusion process such as, the use of correlation and independence, confidence level, contextual information, synchronization
between different modalities, and the optimal modality selection are also highlighted. Finally, we present the open issues
for further research in the area of multimodal fusion. 相似文献
143.
Salah Bouktif Faheem Ahmed Issa Khalil Giuliano Antoniol 《Information and Software Technology》2010,52(12):1298-1311
Context:How can quality of software systems be predicted before deployment? In attempting to answer this question, prediction models are advocated in several studies. The performance of such models drops dramatically, with very low accuracy, when they are used in new software development environments or in new circumstances.ObjectiveThe main objective of this work is to circumvent the model generalizability problem. We propose a new approach that substitutes traditional ways of building prediction models which use historical data and machine learning techniques.MethodIn this paper, existing models are decision trees built to predict module fault-proneness within the NASA Critical Mission Software. A genetic algorithm is developed to combine and adapt expertise extracted from existing models in order to derive a “composite” model that performs accurately in a given context of software development. Experimental evaluation of the approach is carried out in three different software development circumstances.ResultsThe results show that derived prediction models work more accurately not only for a particular state of a software organization but also for evolving and modified ones.ConclusionOur approach is considered suitable for software data nature and at the same time superior to model selection and data combination approaches. It is then concluded that learning from existing software models (i.e., software expertise) has two immediate advantages; circumventing model generalizability and alleviating the lack of data in software-engineering. 相似文献
144.
El-Sayed Ahmed El-Dahshan Tamer Hosny Abdel-Badeeh M. Salem 《Digital Signal Processing》2010,20(2):433-441
This paper presents a hybrid technique for the classification of the magnetic resonance images (MRI). The proposed hybrid technique consists of three stages, namely, feature extraction, dimensionality reduction, and classification. In the first stage, we have obtained the features related to MRI images using discrete wavelet transformation (DWT). In the second stage, the features of magnetic resonance images have been reduced, using principal component analysis (PCA), to the more essential features. In the classification stage, two classifiers have been developed. The first classifier based on feed forward back-propagation artificial neural network (FP-ANN) and the second classifier is based on k-nearest neighbor (k-NN). The classifiers have been used to classify subjects as normal or abnormal MRI human images. A classification with a success of 97% and 98% has been obtained by FP-ANN and k-NN, respectively. This result shows that the proposed technique is robust and effective compared with other recent work. 相似文献
145.
This paper presents a novel compensation method for the coupled fuselage-rotor mode of a Rotary wing Unmanned Aerial Vehicle (RUAV). The presence of stabilizer bar limits the performance of attitude control of an RUAV. In this paper, a Positive Position Feedback (PPF) is introduced to increase the stability margins and allow higher control bandwidth. The identified model is used to design a PPF controller to mitigate the presence of stabilizer bar. Parameters for the linear RUAV model are obtained by performing linear system identification about a few selected points. This identification process gives complete RUAV dynamics and is suitable for designing a Stability Augmentation System (SAS) of an RUAV. The identified parameters of an RUAV model are verified using experimental flight data and can be used to obtain the nonlinear model of an RUAV. The performance of the proposed algorithm is tested using a high-fidelity RUAV simulation model, which is validated through experimental flight data. The closed-loop response of the rotorcraft indicates that the desired attitude performance is achieved while ensuring that the coupled fuselage-rotor mode is effectively compensated without penalizing the phase response. 相似文献
146.
Roman Palenichka Ahmed Lakhssassi Marek Zaremba 《Engineering Applications of Artificial Intelligence》2011,24(5):822-832
This paper presents a method for multi-scale segmentation of surface data using scale-adaptive region growing. The proposed segmentation algorithm is initiated by an unsupervised learning of optimal seed positions through the surface attribute clustering with a two-criterion score function. The seeds are selected as consecutive local maxima of the clustering map, which is computed by an aggregation of the local isotropic contrast and local variance maps. The proposed method avoids typical segmentation errors caused by an inappropriate choice of seed points and thresholds used in the region-growing algorithm. The scale-adaptive threshold estimate is based on the image local statistics in the neighborhoods of seed points. The performance of this method was evaluated on LiDAR surface images. 相似文献
147.
Perimeter discovery in wireless sensor networks 总被引:1,自引:0,他引:1
In this paper, we focus on the perimeter detection problem using wireless sensor networks, as perimeter detection has a wide range of uses in several areas. We present a decentralized localized algorithm where sensor nodes determine if they are located along the perimeter of a wireless sensor network. Our proposed algorithm uses the location neighborhood information in conjunction with the Barycentric technique to determine if the sensor node enclosed by neighboring nodes, and consequently, if it is located within the interior of the wireless sensor network. We define performance metrics to analyze the performance of our approach and the simulation shows that the algorithm gives fairly accurate results. 相似文献
148.
Ahmed M. Al-Adilee 《Information Sciences》2009,179(24):4199-4207
A quantum logic is one of possible mathematical models for non-compatible random events. In this paper, we introduce and study functions called QL-copula and QL-co-copula on a quantum logic and we compare them with the classical definition of copula and co-copula, respectively. Finally, we show several examples of these functions by means of an s-map. 相似文献
149.
A promising electrochemical biosensor was developed by electrodeposition of palladium nanoclusters on polyfuran film modified platinum electrode. This biosensor electrode was used to determine some catecholamines, namely dopamine, epinephrine and norepinephrine, ascorbic acid and paracetamol. The method of formation of the polymer film and deposition of Pd particles plays a key role in the electroactivity of the resulting hybrid material. This sensor effectively resolved the overlapping anodic peaks of ascorbic acid (AA), dopamine (DA) and paracetamol (ACOP) into three well-defined voltammetric peaks in differential pulse voltammetry analysis. The detection limit of DA in the absence and presence of AA and ACOP are eventually the same which indicates that the oxidation processes of DA, AA and ACOP are independent and that the simultaneous measurements of the three analytes are possible without interference. The electrodeposition of Pd on polyfuran improved exceptionally the detection limit about four decades. Moreover, diffusion coefficient measurements confirmed the fast electron transfer kinetics of the electrochemical oxidation of the analyte molecules at the sensor/solution interface. It is very interesting to note that the electrocatalytic effect of PF/Pd composite has been increased to be sometimes 21 times that of the pristine PF which has been considered for a long time to be of low conductivity and attracted low attention as a result of the difficulty of its formation and poor conductivity. 相似文献
150.
Ahmed Fadl Zongqin Zhang Sebastian Geller Jonas Tölke Manfred Krafczyk Donna Meyer 《Microsystem Technologies》2009,15(9):1379-1387
The efficiency of the valve-less rectification micropump depends primarily on the microfluidic diodicity (the ratio of the
backward pressure drop to the forward pressure drop). In this study, different rectifying structures, including the conventional
structures (nozzle/diffuser and Tesla structures), were investigated at very low Reynolds numbers (between 0.2 and 60). The
rectifying structures were characterized with respect to their design, and a numerical approach was illustrated to calculate
the diodicity for the rectifying structures. In this study, the microfluidic diodicity was evaluated numerically for different
rectifying structures including half circle, semicircle, heart, triangle, bifurcation, nozzle/diffuser, and Tesla structures.
The Lattice Boltzmann Method (LBM) was utilized as a numerical method to simulate the fluid flow in the microscale. The results
suggest that at very low Reynolds number flow, rectification and multifunction micropumping may be achievable by using a number
of the presented structures. The results for the conventional structures agree with the reported results. 相似文献