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121.
Motivated by the importance of accurate identification for a range of applications, this paper compares and contrasts the effective and efficient classification of network-based applications using behavioral observations of network-traffic and those using deep-packet inspection.Importantly, throughout our work we are able to make comparison with data possessing an accurate, independently determined ground-truth that describes the actual applications causing the network-traffic observed.In a unique study in both the spatial-domain: comparing across different network-locations and in the temporal-domain: comparing across a number of years of data, we illustrate the decay in classification accuracy across a range of application–classification mechanisms. Further, we document the accuracy of spatial classification without training data possessing spatial diversity.Finally, we illustrate the classification of UDP traffic. We use the same classification approach for both stateful flows (TCP) and stateless flows based upon UDP. Importantly, we demonstrate high levels of accuracy: greater than 92% for the worst circumstance regardless of the application.  相似文献   
122.
Mobile network providers have developed a variety of location-based services (LBSs), such as friend-finder, point of interest services, emergency rescue and many other safety and security services. The protection of location-privacy has consequently become a key aspect to the success of LBSs, since users consider their own physical location and movements highly privacy-sensitive, and demand for solutions able to protect such an information in a variety of environments. The idea behind location-privacy protection is that the individual should be able to set the level at which the location information is released to avoid undesired exploitation by a potential attacker: one of the approaches to this problem is given by the application of spatial obfuscation techniques, actuated by a trusted agent, and consisting in artificial perturbations of the location information collected by sensing technologies, before its disclosure to third parties. In many situations, however, landscape/map information can help a third party to perform Bayesian inference over spatially obfuscated data and to refine the user’s location estimate up to a violation of the original user’s location-privacy requirements. The goal of this paper is to provide a map-dependent obfuscation procedure that enables the release of the maximum possible user’s location information, that does not lead to a violation of the original user’s location-privacy requirements, even when refined through map-based inference.  相似文献   
123.
A recent focus is on creating engaging user experiences with digital products and services such as voicemail. This study aims to design towards increased levels of engagement in voicemail browsing by using the ‘Richness, Control and Engagement’ (RC & E) framework. This framework explains the levels of engagement in terms of the levels of richness and control that are shaped by the features of a product and the user’s expertise. A product was developed that utilized gestures and sound to access digital voicemail contents. An experiment was conducted in which 28 participants interacted with the product while varying (1) the number of features of the user interface, (2) the amount of voicemail content and (3) the type of task. Results showed that the levels of engagement could be predicted according to the levels of richness and control experienced when a task-term was added to the framework. Implications of the refined RC & E framework for interaction design practice are discussed.  相似文献   
124.
We show on a case study from an autonomous aerospace context how to apply a game-based model-checking approach as a powerful technique for the verification, diagnosis, and adaptation of system behaviors based on temporal properties. This work is part of our contribution within the SHADOWS project, where we provide a number of enabling technologies for model-driven self-healing. We propose here to use GEAR, a game-based model checker, as a user-friendly tool that can offer automatic proofs of critical properties of such systems. Although it is a model checker for the full modal μ-calculus, it also supports derived, more user-oriented logics. With GEAR, designers and engineers can interactively investigate automatically generated winning strategies for the games, by this way exploring the connection between the property, the system, and the proof. This work has been partially supported by the European Union Specific Targeted Research Project SHADOWS (IST-2006-35157), exploring a Self-Healing Approach to Designing cOmplex softWare Systems. The project’s web page is at . This article is an extended version of Renner et al. [18] presented at ISoLA 2007, Poitiers, December 2007.  相似文献   
125.
Anti-reflective (AR) boundary conditions (BC) have been introduced recently in connection with fast deblurring algorithms, both in the case of signals and images. Here we extend such BCs to d dimensions (d ≥ 1) and we study in detail the algebra induced by the AR-BCs, with strongly symmetric point spread functions (PSF), both from a structural and computational point of view. The use of the re-blurring idea and the computational features of the AR-algebra allow us to apply Tikhonov-like techniques within O(n d log(n)) arithmetic operations, where n d is the number of pixels of the reconstructed object. Extensive numerical experimentation concerning 2D images and strongly symmetric PSFs confirms the effectiveness of our proposal.   相似文献   
126.
We consider patches that contain any given 3D polynomial curve as a pregeodesic (i.e. geodesic up to reparametrization). A curve is a pregeodesic if and only if its rectifying plane coincides with the tangent plane to the surface, we use this fact to construct ruled cubic patches through pregeodesics and bicubic patches through pairs of pregeodesics. We also discuss the G1 connection of (1,k) patches with abutting pregeodesics.  相似文献   
127.
PURPOSE: To assess the "in vivo" effect of 13-cis-retinoic acid and low dose Ara-C in MDS as well as to establish "in vitro" advantage of retinoid dose-related growth pattern on bone marrow cultures as defined by culture timing and CFU-GM proliferative response. PATIENTS AND METHODS: We evaluated 28 patients diagnosed of MDS according to FAB classification, of whom 4 cases had RA, 8 cases SRA, 14 cases RAEB and 2 cases RAEB-T. Patients who had RA and SRA were treated with oral 13-cis-retinoic acid at doses of 20-40 mg daily for 4 months and those cases with RAEB and RAEB-T had subcutaneous Ara-C at doses of 3 mg/m2 twice a day for 21 days. The "in vivo" and "in vitro" effect of retinoic acid on the haemopoietic differentiation was evaluated by the growth CFU-GM in semisolid cell culture methods. RESULTS: Increasing in vitro concentrations of 13-cis retinoic acid did not enhance the growth of myelodysplastic progenitors. Nevertheless, our study did not find any beneficial therapeutic effect of retinoic compounds in MDS patients. In this study, low-dose Ara-C (3 mg/m2) showed similar effects when compared with higher doses reported by others. Furthermore, in terms of CFU-GM proliferation the concentration of colonies before and after treatment were fairly similar in all but two patients. CONCLUSIONS: The results drawn from our study demonstrated that there is no beneficial advantage of 13-cis-retinoic acid as a differentiation inducing agent on myelodysplastic patients. In contrast, lower doses of Ara-C showed similar effects on haemopoiesis of MDS patients than standard doses of 10-20 mg/m2 but with less side effects.  相似文献   
128.
With reference to the kinematic wave theory coupled with the hypothesis of constant linear velocity for the rating curve, rising limb analytical solutions have been calculated for overland flow, over an Hortonian-infiltrating surface, and sediment discharge. These analytical solutions are certainly easier to use than the numerical integration of the basic equations and they may be used to obtain an initial evaluation of the parameters of more complex models generally devised for complicated cases.Notation a exponent of the Horton law [T–1] - b exponent of the rill erosion equation - B inter-rill erosion coefficient [MLm–2T m–1] - c sediment concentration [ML–3] - c o reference sediment concentration [ML–3] - E I inter-rill erosion [ML–2T–1] - E R rill erosion [ML–2T–1] - f c final infiltration rate of the soil [LT–1] - f o initial infiltration rate of the soil [LT–1] - h flow depth [L] - h o reference flow depth [L] - i infiltration rate [LT–1] - k rill erosion coefficient [ML–1–b T–1] - K integration constant - L() Laplace transformation - m exponent of the inter-rill erosion equation - n Manning's coefficient [L–1/3T] - p rainfall intensity [LT–1] - q water discharge per unit width [L2T–1] - q s sediment discharge per unit width [ML–1T–1] - t time [T] - t p ponding time [T] - x distance along the flow direction [L] Greek Letters coefficient of the stage-discharge equation [L2–T–1] - exponent of the stage-discharge equation - rill erosion coefficient [L–1]  相似文献   
129.
Degenerative disc disease (DDD) has become a significant public health issue worldwide. This can result in loss of spinal function affecting patient health and quality of life. Artificial total disc replacement (A-TDR) is an effective approach for treating symptomatic DDD that compensates for lost functionality and helps patients perform daily activities. However, because current A-TDR devices lack the unique structure and material characteristics of natural intervertebral discs (IVDs), they fail to replicate the multidirectional stiffness needed to match physiological motions and characterize anisotropic behavior. It is still unclear how the multidirectional stiffness of the disc is affected by structural parameters and material characteristics. Herein, a bioinspired intervertebral disc (BIVD-L) based on a representative human lumbar segment is developed. The proposed BIVD-L reproduces the multidirectional stiffness needed for the most common physiological kinematic behaviors. The results demonstrate that the multidirectional stiffness of the BIVD-L can be regulated by structural and material parameters. The results of this research deepen knowledge of the biomechanical behavior of the human lumbar disc and may provide new inspirations for the design and fabrication of A-TDR devices for both engineering and functional applications.  相似文献   
130.
Two-Photon Lithography, thanks to its very high sub-diffraction resolution, has become the lithographic technique par excellence in applications requiring small feature sizes and complex 3D pattering. Despite this, the fabrication times required for extended structures remain much longer than those of other competing techniques (UV mask lithography, nanoimprinting, etc.). Its low throughput prevents its wide adoption in industrial applications. To increase it, over the years different solutions have been proposed, although their usage is difficult to generalize and may be limited depending on the specific application. A promising strategy to further increase the throughput of Two-Photon Lithography, opening a concrete window for its adoption in industry, lies in its combination with holography approaches: in this way it is possible to generate dozens of foci from a single laser beam, thus parallelizing the fabrication of periodic structures, or to engineer the intensity distribution on the writing plane in a complex way, obtaining 3D microstructures with a single exposure. Here, the fundamental concepts behind high-speed Two-Photon Lithography and its combination with holography are discussed, and the literary production of recent years that exploits such techniques is reviewed, and contextualized according to the topic covered.  相似文献   
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