1,693 research outputs found

    Learning without neurons in physical systems

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    Learning is traditionally studied in biological or computational systems. The power of learning frameworks in solving hard inverse-problems provides an appealing case for the development of `physical learning' in which physical systems adopt desirable properties on their own without computational design. It was recently realized that large classes of physical systems can physically learn through local learning rules, autonomously adapting their parameters in response to observed examples of use. We review recent work in the emerging field of physical learning, describing theoretical and experimental advances in areas ranging from molecular self-assembly to flow networks and mechanical materials. Physical learning machines provide multiple practical advantages over computer designed ones, in particular by not requiring an accurate model of the system, and their ability to autonomously adapt to changing needs over time. As theoretical constructs, physical learning machines afford a novel perspective on how physical constraints modify abstract learning theory.Comment: 25 pages, 6 figure

    ORIGAMI-SCISSOR Hinged Geometry Method

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    The diamond origami-scissor hinged pattern marks a new type of thick origami that can not only fold and unfold, but also expand and contract (project below). This was done by applying the ‘form generation method of relative ratios’ for two-bar scissors to the thick origami. This research tests whether this method can be extended and generalized to other types of origami. The origami-scissor hinged geometry method is here applied to the waterbomb of thick panels making a waterbomb origami-scissor hinged pattern. While the waterbomb origami of thick panels has one degree of freedom, the waterbomb origami-scissor hinged pattern has two degrees of freedom as it can independently fold and unfold as an origami, and expand and contract as a scissor hinged structure. This creates a new research branch of expandable thick origami. The ‘form generation method of relative ratios’ (FGMORR) [Rivas-Adrover 17] has been applied to the ‘origami of thick panels’ [Chen et al. 15] because this method to make thick origami can be extended and generalized to different types of origami, and therefore the origami-scissor hinged geometry method can also be applied to all these different types of origami. A critical condition is that the thick origami has to be made of equal or proportional thicknesses so that when translating that geometry with scissors the end nodes match. Another condition is that the pantographs that mark the creases and join different origami faces must have an equal morphology and bilateral symmetry. Automation of this method will be investigated with Grasshopper for Rhinoceros. Origami-scissor hinged patterns provide an extra degree of freedom, therefore origami patterns that could be folded can now also contract and occupy much smaller volumes. This would be useful in applications where a high ratio of deployed-to stowed volume is required such as space applications, earthbound transportable applications, and to create adaptable spaces and transformable environments in permanent architecture

    A Survey on Biometrics and Cancelable Biometrics Systems

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    Now-a-days, biometric systems have replaced the password or token based authentication system in many fields to improve the security level. However, biometric system is also vulnerable to security threats. Unlike password based system, biometric templates cannot be replaced if lost or compromised. To deal with the issue of the compromised biometric template, template protection schemes evolved to make it possible to replace the biometric template. Cancelable biometric is such a template protection scheme that replaces a biometric template when the stored template is stolen or lost. It is a feature domain transformation where a distorted version of a biometric template is generated and matched in the transformed domain. This paper presents a review on the state-of-the-art and analysis of different existing methods of biometric based authentication system and cancelable biometric systems along with an elaborate focus on cancelable biometrics in order to show its advantages over the standard biometric systems through some generalized standards and guidelines acquired from the literature. We also proposed a highly secure method for cancelable biometrics using a non-invertible function based on Discrete Cosine Transformation (DCT) and Huffman encoding. We tested and evaluated the proposed novel method for 50 users and achieved good results

    Performance comparison of intrusion detection systems and application of machine learning to Snort system

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    This study investigates the performance of two open source intrusion detection systems (IDSs) namely Snort and Suricata for accurately detecting the malicious traffic on computer networks. Snort and Suricata were installed on two different but identical computers and the performance was evaluated at 10 Gbps network speed. It was noted that Suricata could process a higher speed of network traffic than Snort with lower packet drop rate but it consumed higher computational resources. Snort had higher detection accuracy and was thus selected for further experiments. It was observed that the Snort triggered a high rate of false positive alarms. To solve this problem a Snort adaptive plug-in was developed. To select the best performing algorithm for Snort adaptive plug-in, an empirical study was carried out with different learning algorithms and Support Vector Machine (SVM) was selected. A hybrid version of SVM and Fuzzy logic produced a better detection accuracy. But the best result was achieved using an optimised SVM with firefly algorithm with FPR (false positive rate) as 8.6% and FNR (false negative rate) as 2.2%, which is a good result. The novelty of this work is the performance comparison of two IDSs at 10 Gbps and the application of hybrid and optimised machine learning algorithms to Snort

    Gait recognition and understanding based on hierarchical temporal memory using 3D gait semantic folding

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    Gait recognition and understanding systems have shown a wide-ranging application prospect. However, their use of unstructured data from image and video has affected their performance, e.g., they are easily influenced by multi-views, occlusion, clothes, and object carrying conditions. This paper addresses these problems using a realistic 3-dimensional (3D) human structural data and sequential pattern learning framework with top-down attention modulating mechanism based on Hierarchical Temporal Memory (HTM). First, an accurate 2-dimensional (2D) to 3D human body pose and shape semantic parameters estimation method is proposed, which exploits the advantages of an instance-level body parsing model and a virtual dressing method. Second, by using gait semantic folding, the estimated body parameters are encoded using a sparse 2D matrix to construct the structural gait semantic image. In order to achieve time-based gait recognition, an HTM Network is constructed to obtain the sequence-level gait sparse distribution representations (SL-GSDRs). A top-down attention mechanism is introduced to deal with various conditions including multi-views by refining the SL-GSDRs, according to prior knowledge. The proposed gait learning model not only aids gait recognition tasks to overcome the difficulties in real application scenarios but also provides the structured gait semantic images for visual cognition. Experimental analyses on CMU MoBo, CASIA B, TUM-IITKGP, and KY4D datasets show a significant performance gain in terms of accuracy and robustness
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