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51.
While several service discovery protocols and standards have been proposed for supporting service discovery from mobile devices,
this remains a challenging problem. In many cases, mobile clients may discover services which they consider relevant but soon
realize that such services are not completely usable on their mobile devices due to compatibility and interoperability issues.
Without integrating device capabilities into the discovery process, or a device-aware mobile service discovery, it becomes
extremely difficult to determine whether discovered services may or may not function properly within the device’s constraints.
This paper introduces a solution known as MobiEureka, a mobile device-aware system for enhancing the discovery of mobile web
services from mobile devices. Experimental validation, results, and analysis of the introduced ideas are discussed. 相似文献
52.
Packages are important high-level organizational units for large object-oriented systems. Package-level metrics characterize the attributes of packages such as size, complexity, and coupling. There is a need for empirical evidence to support the collection of these metrics and using them as early indicators of some important external software quality attributes. In this paper, three suites of package-level metrics (Martin, MOOD and CK) are evaluated and compared empirically in predicting the number of pre-release faults and the number of post-release faults in packages. Eclipse, one of the largest open source systems, is used as a case study. The results indicate that the prediction models that are based on Martin suite are more accurate than those that are based on MOOD and CK suites across releases of Eclipse. 相似文献
53.
In this paper we present a technique for the automatic recognition of Arabic (Indian) bank check digits based on features
extracted by using the Log Gabor filters. The digits are classified by using the K-Nearest Neighbor (K-NN), Hidden Markov
Models (HMM) and Support Vector Machines (SVM) classifiers. An extensive experimentation is conducted on the CENPARMI data,
a database consisting of 7390 samples of Arabic (Indian) digits for training and 3035 samples for testing extracted from real
bank checks. The data is normalized to a height of 64 pixels, maintaining the aspect ratio. Log Gabor filters with several
scales and orientations are used. In addition, the filtered images are segmented into different region sizes for feature extraction.
Recognition rates of 98.95%, 98.75%, 98.62%, 97.21% and 94.43% are achieved with SVM, 1-NN, 3-NN, HMM and NM classifiers,
respectively. These results significantly outperform published work using the same database. The misclassified digits are
evaluated subjectively and results indicate that human subjects misclassified 1/3 of these digits. The experimental results,
including the subjective evaluation of misclassified digits, indicate the effectiveness of the selected Log Gabor filters
parameters, the implemented image segmentation technique, and extracted features for practical recognition of Arabic (Indian)
digits. 相似文献
54.
Mostafa Sabzekar Hadi Sadoghi Yazdi Mahmoud Naghibzadeh 《Neural computing & applications》2011,20(5):671-685
Real-world data collected for computer-based applications are frequently impure. Differentiation of outliers and noisy data
from normal ones is a major task in data mining applications. On the other hand, elimination of noisy and outlier data from
training samples of a dataset may lead to over-fitting or information loss. A fuzzy support vector machine (FSVM) provides
an effective means to deal with this problem. It reduces the effect of the noisy data and outliers by using a fuzzy membership
functions. In this paper, a new formation for SVMs is introduced that considers importance degrees for training samples. The
constraints of the SVM are converted to fuzzy inequalities. The proposed method, RSVM, shows better efficiency in the classification
of data in different domains. Especially, using the proposed RSVM for multi-class classification of arrhythmia disease is
presented at the end of this paper as a practical case study to show the effectiveness of the proposed system. 相似文献
55.
Tarek Sheltami Anas Al-Roubaiey Elhadi Shakshuki Ashraf Mahmoud 《Multimedia Systems》2009,15(5):273-282
Mobile Ad-hoc NETworks (MANET) are infrastructureless networks where self-configuring mobile nodes are connected by wireless
links. Because of its decentralized operation, these nodes rely on each other to store and forward packets. Video transmission
over MANETs is more challenging than over conventional wireless networks due to rapid topology changes and lack of central
administration. Most of the proposed MANET protocols assume that all nodes are working within a cooperative and friendly network
context. However, misbehaving nodes that exhibit abnormal behaviors can disrupt the network operation and affect the network
availability by refusing to cooperate to route packets due to their selfish or malicious behavior. In this paper, we examine
the effect of packet dropping attacks on video transmission over MANETs. We also study the effects of mitigation using intrusion
detection systems to MANET in presence of video traffic. To the best of our knowledge, this is the first attempt to study
multimedia over such environments. We propose a novel intrusion detection system, which is an adaptive acknowledgment scheme
(AACK) with the ability to detect misbehaved nodes and avoid them in other transmissions. The aim of AACK scheme is to overcome
watchdog weaknesses due to collisions and limited transmission power and also to improve TWOACK scheme. To demonstrate the
performance of our proposed scheme, simulation experiments are performed. The results of our experiments show that MPEG4 is
more suitable for our simulation environment than H264 video traffic. The simulation results show that AACK scheme provides
better network performance with less overhead than other schemes; it also shows that AACK outperforms both TWOACK and watchdog
in video transmission applications in the presence of misbehaving nodes. 相似文献
56.
User Activities Outliers Detection; Integration of Statistical and Computational Intelligence Techniques 下载免费PDF全文
In this article, a hybrid technique for user activities outliers detection is introduced. The hybrid technique consists of a two‐stage integration of principal component analysis and fuzzy rule‐based systems. In the first stage, the Hamming distance is used to measure the differences between different activities. Principal component analysis is then applied to the distance measures to find two indices of Hotelling's T2 and squared prediction error. In the second stage of the process, the calculated indices are provided as inputs to the fuzzy rule‐based systems to model them heuristically. The model is used to identify the outliers and classify them. The proposed system is tested in real home environments, equipped with appropriate sensory devices, to identify outliers in the activities of daily living of the user. Three case studies are reported to demonstrate the effectiveness of the proposed system. The proposed system successfully identifies the outliers in activities distinguishing between the normal and abnormal behavioral patterns. 相似文献
57.
Lounis Kessal Nicolas Abel Si Mahmoud Karabernou Didier Demigny 《Journal of Real-Time Image Processing》2008,3(3):131-147
Technology evolution makes possible the integration of heterogeneous components as programmable elements (processors), hardware
dedicated blocks, hierarchical memories and buses. Furthermore, an optimized reconfigurable logic core embedded within a System-on-Chip
will associate the performances of dedicated architecture and the flexibility of programmable ones. In order to increase performances,
some of the applications are carried out in hardware, using dynamically reconfigurable logic, rather than software, using
programmable elements. This approach offers a suitable hardware support to design malleable systems able to adapt themselves
to a specific application. This article makes a synthesis of the Ardoise project. The first objective of Ardoise project was
to design and to produce a dynamically reconfigurable platform based on commercial FPGAs. The concept of dynamically reconfigurable
architecture depends partially on new design methodologies elaboration as well as on the programming environment. The platform
architecture was designed to be suitable for real-time image processing. The article outlines mainly the Ardoise tools aspect:
development environment and real-time management of the hardware tasks. The proposed methodology is based on a dynamic management
of tasks according to an application scenario written using C++ language.
相似文献
Lounis KessalEmail: |
58.
EL Wallace DM Surgenor HS Hao J An RH Chapman WH Churchill 《Canadian Metallurgical Quarterly》1993,33(2):139-144
A poor response to L-DOPA in addition to parkinsonian, cerebellar, and autonomic signs is commonly regarded as indicative of clinical multiple system atrophy (MSA). We compared the motor response to a single oral administration of 250 mg L-DOPA/25 mg carbidopa in eight MSA patients and eight Parkinson's disease (PD) patients with the "on-off" phenomenon, evaluating L-DOPA peripheral pharmacokinetics. Motor response was consistently good in all PD patients, but only four MSA patients had a (moderate) response. Pharmacokinetic parameters did not differ between the groups. The varying extent of putaminal damage could be responsible for the differing motor response to L-DOPA in MSA patients. 相似文献
59.
60.
Global decentralized discrete sliding mode control of a class of interconnected system using only output information is considered in this paper. Matched and unmatched uncertainties as well as known and unknown interconnections are treated. Bounded time-varying delays are considered within the subsystems and through interconnections. The stability of the reduced-order interconnected systems is analyzed using the Lyapunov–Kraszovskii approach and a novel reachability condition of the composite sliding surfaces is established. The resultant dynamics are proved to be globally asymptotically stable. Simulations show the efficacy of the proposed scheme. 相似文献