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As users' preferences shift continuously, recommendation system has to learn quickly from them. It is an interesting online learning problem as recommender does not have any prior knowledge about the distribution of items over the users. In this work, we generate a small recommendation set from a large number of items, with an intention that at least one of recommended items would satisfy the user...
Security is required in order to defend information from unauthorized person on the network. Therefore, securely exchanging data over the internet is vital. In this context, cryptography is used that transmute facts from its under stable form into an indecipherable form by using various encryption techniques. Play air cipher is the form of block cipher which has no limit on the number of characters...
This paper presents an improvised approach for plain text password encryption in the server's database. One of the major aspect of password protection issue is to secure it by means of encryption process. In cryptanalysis, a dictionary attacks or brute force attacks are the most common ways of cracking passwords. A new approach for improvising the scheme of password encryption is using the process...
Nowadays, ocean wave energy is one of the world's most powerful forms of energy and extracting wave energy from seas has been proven to be very difficult although various technologies and finding an accurate identification of sea wave energy conversion system is very important to achieve an efficient model for all converter parameters. This article presents an Adaptive particle swarm for parameters...
In the present work, an adaptive backstepping algorithm is developed in order to counteract the effects of disturbances. These disturbances are modeled as a constant force in the translational model part and as a constant torque in the orientation model part. We make the deduction of the mathematical expression for the proposed control algorithm and also we show its performance in simulation. Additionally,...
Modern digital systems are growing in size and complexity, introducing significant organizational and verification challenges in the design cycle. Verification today takes as much as 70% of the design time with debugging being responsible for half of this effort. Automation has mitigated part of the resource-intensive nature of rectifying erroneous designs. Nevertheless, most tools target failures...
A problem with distance fields is that the performance cost for computing a distance field is quite extensive. The main contribution of this paper is proposing multi-threaded signed distance fields based on special partition which accelerate the computing speed. Here we use the uniform grid to divide the space. We convert distance values to color and create rendering slices along x, y, z axis to visualize...
The aim of any science is to advance the state-of-the-art knowledge via a rigorous investigation and analysis of empirical observations, as well as the development of new theoretical frameworks. Data acquisition and ultimately the extraction of novel knowledge, is therefore the foundation of any scientific advance. However, with the increasing creation of data in various forms and shapes, identifying...
The atomic force microscopy (AFM) is an important innovation in the sample imaging fields, the signals extracted from the AFM such as the force as function of the indentation and the friction as function of the indentation can be used to extract many chemical and mechanical properties of the sample. Nanoscientists analyze these signals manually; the aim of this article is to find new algorithms to...
This paper addresses the problem of segregation of groups of heterogeneous units in robot swarms. We propose a controller that can drive robots in a way that each group composed of robots of a similar type will form clusters while maintaining segregation from other groups. The approach is based on abstractions created to represent each group of robots and an artificial potential function used to segregate...
In this paper, we present an efficient algorithm for solving optimization problems, which is based on gravitational search algorithm (GSA). In the proposed technique, called Two-Step method, the best solution of position will be considered and calculated with another agents, and the fitness of extended agents are compared with agents in original gravitation field, which can reinforce the exploration...
This paper presents a recursive and parallel formulation for the dynamics simulation of large articulated robotic systems based on the Hamilton's canonical equations. Although Hamilton's canonical equations exhibit many advantageous features compared to their acceleration based counterparts, it appears that there is a lack of dedicated parallel algorithms for multi-rigid body dynamics simulation based...
This work studied three-dimensional path planning of rotary-wing flying robot in free flight model. Path planning algorithm combining artificial potential field with ant colony algorithm was proposed for the complex problem in three-dimensional environment. These two algorithms were integrated and optimized for three-dimensional environment with advantages and disadvantages of these two algorithm...
Although Ilizarov technique and external fixators have been popular applied in bone fractures and orthopaedic surgery currently, there are few literatures about laws of bone-remodelling after osteotomy when applied external fixation system based on Wolff's law. However, Wolff's law is one of the most basic theories in bone biomechanics and fracture healing Therefore, exploring the healing mechanism...
Files are often compressed for efficiency. RAR is a common archive file format that supports data compression, error recovery and file spanning. RAR uses classic symmetric encryption algorithm SHA-1 hashing and AES algorithm for encryption. These two algorithms cannot be cracked, so the only method of password recovery is brute force, which is very time-consuming. In this paper, we present an approach...
The computational complexity of discord discovery is O(m2), where m is the size of time series. Many promising methods were proposed to resolve this compute-intensive problem. These methods sequentially discover discords on standalone machine. The limited capability of standalone machine in terms of computing and memory capacity hinders these methods in discovering discords from large dataset in reasonable...
Nowadays, electronics systems design is a complex process. A design-and-reuse model has been adopted, and the vast majority of designers integrates third party intellectual property (IP) cores in their design in order to reduce time to market. Due to their immaterial form and high market value, IP cores are exposed to threats such as cloning and illegal copying. In order to fight these threats, we...
This paper presents a Markov chain based approach for the probabilistic density control of a swarm of autonomous “ON-OFF” agents. The proposed approach specifies the time evolution of the probabilistic density distribution by using a Markov chain, which guides the swarm to a desired steady-state final distribution, while satisfying the prescribed ergodicity and safety constraints. Prior research has...
This paper presents a self-learning strategy for an artificial cognitive control based on a reinforcement learning strategy, in particular, an on-line version of a Q-learning algorithm. One architecture for artificial cognitive control was initially reported in [1], but without an effective self-learning strategy in order to deal with nonlinear and time variant behavior. The anticipation mode (i.e...
Human will have their own preferences when they are walking such as direction in their movement, destination and walking speed. These preferences and walking patterns can be affected by several factors including psychological behavior of evading other people or obstacle to avoid any collision by exerting certain repulsion forces. To demonstrate plausible human movement pattern, agent simulation model...
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