共查询到20条相似文献,搜索用时 15 毫秒
1.
This article presents Andromaly—a framework for detecting malware on Android mobile devices. The proposed framework realizes a Host-based Malware Detection System that continuously monitors various features and events obtained from the mobile device and then applies Machine Learning anomaly detectors to classify the collected data as normal (benign) or abnormal (malicious). Since no malicious applications are yet available for Android, we developed four malicious applications, and evaluated Andromaly’s ability to detect new malware based on samples of known malware. We evaluated several combinations of anomaly detection algorithms, feature selection method and the number of top features in order to find the combination that yields the best performance in detecting new malware on Android. Empirical results suggest that the proposed framework is effective in detecting malware on mobile devices in general and on Android in particular. 相似文献
2.
Neural Computing and Applications - This research paper presents MLDroid—a web-based framework—which helps to detect malware from Android devices. Due to increase in the popularity of... 相似文献
3.
Face detection and landmark localization have been extensively investigated and are the prerequisite for many face related applications, such as face recognition and 3D face reconstruction. Most existing methods address only one of the two problems. In this paper, we propose a coupled encoder–decoder network to jointly detect faces and localize facial key points. The encoder and decoder generate response maps for facial landmark localization. Moreover, we observe that the intermediate feature maps from the encoder and decoder represent facial regions, which motivates us to build a unified framework for multi-scale cascaded face detection by coupling the feature maps. Experiments on face detection using two public benchmarks show improved results compared to the existing methods. They also demonstrate that face detection as a pre-processing step leads to increased robustness in face recognition. Finally, our experiments show that the landmark localization accuracy is consistently better than the state-of-the-art on three face-in-the-wild databases. 相似文献
4.
In comparison with the relatively slow progress of battery technology, semiconductor memory has improved much more rapidly, making storage a less critical limiting factor in designing low power embedded systems such as PDAs. To exploit such technology trends, we present a novel framework, a joint encoder–decoder framework (JEDF), which allows the decoder to tradeoff energy and memory consumption without sacrificing playback quality. We employ sum-of-powers-of-two (SOPOT) technique, an approximate signal processing (ASP) technique, in an MPEG AAC decoder to reduce the computational workload. The SOPOT introduces additional ASP noise (in the decoder) on top of the quantization noise introduced in the process of lossy compression (in the encoder). The sum of these two kinds of noise may become audible when it exceeds the masking threshold. We tackle this problem from a new perspective: the proposed JEDF allows the ASP and quantization noises to be shaped jointly to match the masking threshold. In the case that the perceptual room between the masking threshold and the quantization noise is insufficient for the ASP noise, the JEDF can reduce the quantization noise level which results in an increase in bitrate. To implement the proposed scheme, we have developed two new techniques: (1) SOPOT truncation noise shaping; (2) truncation noise allocation based on a perceptual model. Experimental results show the effectiveness of our approach. 相似文献
5.
In this paper a special class of k-step methods of order k+1 with two free parameters up to order 9 are established. The stability analysis of the P–C scheme is investigated. The coefficients of our class and the values of the parameters for getting A0-stable schemes are tabulated. The relation between the parameters for obtaining L( α)-stable formula is determined. A comparison between the stability region and the error estimation for the fourth-order of our scheme and Cash's scheme is carried on. 相似文献
6.
Dyson–Schwinger equations are important tools for non-perturbative analyses of quantum field theories. For example, they are very useful for investigations in quantum chromodynamics and related theories. However, sometimes progress is impeded by the complexity of the equations. Thus automating parts of the calculations will certainly be helpful in future investigations. In this article we present a framework for such an automation based on a C++ code that can deal with a large number of Green functions. Since also the creation of the expressions for the integrals of the Dyson–Schwinger equations needs to be automated, we defer this task to a Mathematica notebook. We illustrate the complete workflow with an example from Yang–Mills theory coupled to a fundamental scalar field that has been investigated recently. As a second example we calculate the propagators of pure Yang–Mills theory. Our code can serve as a basis for many further investigations where the equations are too complicated to tackle by hand. It also can easily be combined with DoFun, a program for the derivation of Dyson–Schwinger equations. 1Program summaryProgram title: CrasyDSE Catalogue identifier: AEMY _v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEMY_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 49030 No. of bytes in distributed program, including test data, etc.: 303958 Distribution format: tar.gz Programming language: Mathematica 8 and higher, C++. Computer: All on which Mathematica and C++ are available. Operating system: All on which Mathematica and C++ are available (Windows, Unix, Mac OS). Classification: 11.1, 11.4, 11.5, 11.6. Nature of problem: Solve (large) systems of Dyson–Schwinger equations numerically. Solution method: Create C++ functions in Mathematica to be used for the numeric code in C++. This code uses structures to handle large numbers of Green functions. Unusual features: Provides a tool to convert Mathematica expressions into C++ expressions including conversion of function names. Running time: Depending on the complexity of the investigated system solving the equations numerically can take seconds on a desktop PC to hours on a cluster. 相似文献
7.
Neural Computing and Applications - Automatic vehicle detection in urban traffic surveillance is an important and urgent issue, since it provides necessary information for further processing.... 相似文献
8.
Since an increasing amount of data is generated and collected in real life, clustering is more frequently applied to process these unlabeled data in practical problems. Due to the simple similarity measure of conventional clustering methods, they are unable to achieve good performance on current big data. With the popularity of deep learning, deep clustering has been developed in recent years and obtained remarkable results. However, they have complex architecture and consume numerous computational resources, which goes against the migration to edge devices. Therefore, methods with low cost are required to satisfy edge computing, which is the trend of development. In this paper, we propose GAN–SOM as a new architecture for clustering based on deep learning. A SOM-similar network is designed to simultaneously implement encoding and clustering purposes on data samples, which is jointly trained with a GAN to optimizes a new defined clustering loss. We also utilize self-attention mechanism and spectral normalization in the GAN architecture to enhance effects of generated data, which aims to achieve better clustering results. The experimental results compared with other clustering baselines with deep learning verify that our method maintains high clustering metrics while saving computational cost significantly. 相似文献
9.
A promising line of research for radar systems attempts to optimize the detector thresholds so as to maximize the overall performance of a radar detector–tracker pair. In the present work, we attempt to move in a direction to fulfill this promise by considering a particular dynamic optimization scheme which relies on a non-simulation performance prediction (NSPP) methodology for the probabilistic data association filter (PDAF), namely, the modified Riccati equation (MRE). By using a suitable functional approximation, we propose a closed-form solution for the special case of a Neyman–Pearson (NP) detector. The proposed solution replaces previously proposed iterative solution formulations and results in dramatic improvement in computational complexity without sacrificed system performance. Moreover, it provides a theoretical lower bound on the detection signal-to-noise ratio (SNR) concerning when the whole tracking system should be switched to the track before detect (TBD) mode. 相似文献
10.
In this work, a reduced order multidisciplinary optimization procedure is developed to enable efficient, low frequency, undamped
and damped, fully coupled, structural–acoustic optimization of interior cavities backed by flexible structural systems. This
new method does not require the solution of traditional eigen value based problems to reduce computational time during optimization, but are instead based on computation of Arnoldi
vectors belonging to the induced Krylov Subspaces. The key idea of constructing such a reduced order model is to remove the
uncontrollable, unobservable and weakly controllable, observable parts without affecting the noise transfer function of the
coupled system. In a unified approach, the validity of the optimization framework is demonstrated on a constrained composite
plate/prism cavity coupled system. For the fully coupled, vibro–acoustic, unconstrained optimization problem, the design variables
take the form of stacking sequences of a composite structure enclosing the acoustic cavity. The goal of the optimization is
to reduce sound pressure levels at the driver’s ear location. It is shown that by incorporating the reduced order modelling
procedure within the optimization framework, a significant reduction in computational time can be obtained, without any loss
of accuracy—when compared to the direct method. The method could prove as a valuable tool to analyze and optimize complex
coupled structural–acoustic systems, where, in addition to fast analysis, a fine frequency resolution is often required. 相似文献
11.
Mesh of trees (MOT) is well known for its small diameter, high bisection width, simple decomposability and area universality. On the other hand, OTIS (Optical Transpose Interconnection System) provides an efficient optoelectronic model for massively parallel processing system. In this paper, we present OTIS-MOT as a competent candidate for a two-tier architecture that can take the advantages of both the OTIS and the MOT. We show that an n4-n^{4}_{-} processor OTIS-MOT has diameter 8log n ∗+1 (The base of the logarithm is assumed to be 2 throughout this paper.) and fault diameter 8log n+2 under single node failure. We establish other topological properties such as bisection width, multiple paths and the modularity. We show that many communication as well as application algorithms can run on this network in comparable time or even faster than other similar tree-based two-tier architectures. The communication algorithms including row/column-group broadcast and one-to-all broadcast are shown to require O(log n) time, multicast in O( n 2log n) time and the bit-reverse permutation in O( n) time. Many parallel algorithms for various problems such as finding polynomial zeros, sales forecasting, matrix-vector multiplication and the DFT computation are proposed to map in O(log n) time. Sorting and prefix computation are also shown to run in O(log n) time. 相似文献
12.
Image denoising is the problem that aims at recovering a clean image from a noisy counterpart. A promising solution for image denoising is to employ an appropriate deep neural network to learn a hierarchical mapping function from the noisy image to its clean counterpart. This mapping function, however, is generally difficult to learn since the potential feature space of the noisy patterns can be huge. To overcome this difficulty, we propose a separation–aggregation strategy to decompose the noisy image into multiple bands, each of which exhibits one kind of pattern. Then a deep mapping function is learned for each band and the mapping results are ultimately assembled to the clean image. By doing so, the network only needs to deal with the compositing components of the noisy image, thus makes it easier to learn an effective mapping function. Moreover, as any image can be viewed as a composition of some basic patterns, our strategy is expected to better generalize to unseen images. Inspired by this idea, we develop a separation–aggregation network. The proposed network consists of three blocks, namely a convolutional separation block that decomposes the input into multiple bands, a deep mapping block that learns the mapping function for each band, and a band aggregation block that assembles the mapping results. Experimental results demonstrate the superiority of our strategy over counterparts without image decomposition. 相似文献
13.
The Union–Find data structure for maintaining disjoint sets is one of the best known and widespread data structures, in particular the version with constant-time Union and efficient Find. Recently, the question of how to handle deletions from the structure in an efficient manner has been taken up, first by Kaplan et al. (2002) [2] and subsequently by Alstrup et al. (2005) [1]. The latter work shows that it is possible to implement deletions in constant time, without affecting adversely the asymptotic complexity of other operations, even when this complexity is calculated as a function of the current size of the set.In this note we present a conceptual and technical simplification of the algorithm, which has the same theoretical efficiency, and is probably more attractive in practice. 相似文献
14.
This paper proposes a hybrid genetic algorithm (GA) to solve the capacitated location–routing problem. The proposed algorithm follows the standard GA framework using local search procedures in the mutation phase. Computational evaluation was carried out on three sets of benchmark instances from the literature. Results show that, although relatively simple, the proposed algorithm is effective, providing competitive results for benchmark instances within reasonable computing time. 相似文献
15.
The fuzzy min–max (FMM) network is a supervised neural network classifier that forms hyperboxes for classification and prediction. In this paper, we propose modifications to FMM in an attempt to improve its classification performance when a small number of large hyperboxes are formed in the network. Given a new input pattern, in addition to measuring the fuzzy membership function of the input pattern to the hyperboxes formed in FMM, an Euclidean distance measure is introduced for predicting the target class associated with the new input pattern. A rule extraction algorithm is also embedded into the modified FMM network. A confidence factor is calculated for each FMM hyperbox, and a user-defined threshold is used to prune the hyperboxes with low confidence factors. Fuzzy if– then rules are then extracted from the pruned network. The benefits of the proposed modifications are twofold, viz., to improve the performance of FMM when large hyperboxes are formed in the network; to facilitate the extraction of a compact rule set from FMM to justify its predictions. To assess the effectiveness of modified FMM, two benchmark pattern classification problems are experimented, and the results from different methods published in the literature are compared. In addition, a fault detection and classification problem with a set of real sensor measurements collected from a power generation plant is evaluated using modified FMM. The results obtained are analyzed and explained, and implications of the modified FMM network as a useful fault detection and classification tool in real environments are discussed. 相似文献
16.
Network intrusion detection research work that employed KDDCup 99 dataset often encounter challenges in creating classifiers
that could handle unequal distributed attack categories. The accuracy of a classification model could be jeopardized if the
distribution of attack categories in a training dataset is heavily imbalanced where the rare categories are less than 2% of
the total population. In such cases, the model could not efficiently learn the characteristics of rare categories and this
will result in poor detection rates. In this research, we introduce an efficient and effective approach in dealing with the
unequal distribution of attack categories. Our approach relies on the training of cascaded classifiers using a dichotomized
training dataset in each cascading stage. The training dataset is dichotomized based on the rare and non-rare attack categories.
The empirical findings support our arguments that training cascaded classifiers using the dichotomized dataset provides higher
detection rates on the rare categories as well as comparably higher detection rates for the non-rare attack categories as
compared to the findings reported in other research works. The higher detection rates are due to the mitigation of the influence
from the dominant categories if the rare attack categories are separated from the dataset. 相似文献
17.
Traditional information system development approaches separate the domain model from the system model and then focus on the transformation between them. They are not, however, useful in rapid development of virtual organisations. This paper proposes a simulation-based development framework for establishing such organisations. It consists of a federation–agent–workflow (FAW) model, a set of rules for establishing the mapping from the domain into the virtual organisation, a set of management services, and a macro development process. Basic elements of the model are agents, which can perform active domain behaviour, and they are organised as autonomous federations. Agents within the same federation perform relevant tasks according to an overall workflow. Domain organisation is simulated by the multi-level agents whose behaviour are driven by a nested-workflow mechanism. The framework unifies the traditional domain organisation and information system model into a virtual organisation model, and this allows users to develop intuitive virtual organisations from the viewpoint of the domain. A comparison between the framework and the traditional information system approaches shows that the framework provides a simpler development process, so it meets the needs of virtual organisations for rapid and mobile development. 相似文献
18.
pantograph–catenary system is one of the critical components used in electrical trains. It ensures the transmission of the electrical energy to the train taken from the substation that is required for electrical trains. The condition monitoring and early diagnosis for pantograph–catenary systems are very important in terms of rail transport disruption. In this study, a new method is proposed for arc detection in the pantograph–catenary system based signal processing and S-transform. Arc detection and condition monitoring were achieved by using current signals received from a real pantograph–catenary system. Firstly, model based current data for pantograph–catenary system is obtained from Mayr arc model. The method with S-transform is developed by using this current data. Noises on the current signal are eliminated by applying a low pass filter to the current signal. The peak values of the noiseless signals are determined by taking absolute values of these signals in a certain frequency range. After the data of the peak points has been normalized, a new signal will be obtained by combining these points via a linear interpolation method. The frequency-time analysis was realized by applying S-transform on the signal obtained from peak values. Feature extraction that obtained by S-matrix was used in the fuzzy system. The current signal is detected the contdition as healthy or faulty by using the outputs of the fuzzy system. Furthermore the real-time processing of the proposed method is examined by applying to the current signal received from a locomotive. 相似文献
19.
In human–robot interaction, the robot controller must reactively adapt to sudden changes in the environment (due to unpredictable human behaviour). This often requires operating different modes, and managing sudden signal changes from heterogeneous sensor data. In this paper, we present a multimodal sensor-based controller, enabling a robot to adapt to changes in the sensor signals (here, changes in the human collaborator behaviour). Our controller is based on a unified task formalism, and in contrast with classical hybrid visicn–force–position control, it enables smooth transitions and weighted combinations of the sensor tasks. The approach is validated in a mock-up industrial scenario, where pose, vision (from both traditional camera and Kinect), and force tasks must be realized either exclusively or simultaneously, for human–robot collaboration. 相似文献
20.
Cutset algorithms have been well documented in the operations research literature. A directed graph is used to model the network, where each node and arc has an associated cost to cut or remove it from the graph. The problem considered in this paper is to determine all minimum cost sets of nodes and/or arcs to cut so that no directed paths exist from a specified source node s to a specified sink node t. By solving the dual maximum flow problem, it is possible to construct a binary relation associated with an optimal maximum flow such that all minimum cost s– t cutsets are identified through the set of closures for this relation. The key to our implementation is the use of graph theoretic techniques to rapidly enumerate this set of closures. Computational results are presented to suggest the efficiency of our approach. Scope and purposeThis paper describes the technical details of a network flow algorithm used to find all minimum cost s– t cutsets in any network topology. The motivation for this work was to provide additional automated analysis capability to a military network targeting system. Specifically, the problem is to identify a minimum cost set of nodes and/or arcs that when removed from the network, will disconnect a selected pair of origin–destination nodes. Algorithms for solving this problem are well understood, with an active research thrust in both the operations research and computer science academic communities in developing more efficient algorithms for larger networks. The main contribution of this paper is in extending these algorithms to quickly find all minimum cost cutset solutions. The implementation described in this paper outperformed conventional methods by several orders of magnitude on networks having thousands of nodes and arcs, with empirical solution times that grew linearly with the network size. The results translate to a real-time cutset analysis capability to support military targeting applications. 相似文献
|