Nguyen Thanh Tung

Segmentation of dental X-ray images in medical imaging using neutrosophic orthogonal matrices

Abstract Over the last few decades, the advance of new technologies in computer equipment, cameras and medical devices became a starting point for the shape of medical imaging systems. Since then, many new medical devices, e.g. the X-Ray machines, computed tomography scans, magnetic resonance imaging, etc., accompanied with operational algorithms inside has contributed greatly to successful diagnose of clinical cases. Enhancing the accuracy of segmentation, which plays an important role in the recognition of disease patterns, has been the focus of various researches in recent years. Segmentation using advanced fuzzy clustering to handle the problems of common boundaries between clusters would tackle many challenges in medical imaging. In this paper, we propose a new fuzzy clustering algorithm based on the neutrosophic orthogonal matrices for segmentation of dental X-Ray images. This algorithm transforms image data into a neutrosophic set and computes the inner products of the cutting matrix of input. Pixels are then segmented by the orthogonal principle to form clusters. The experimental validation on real dental datasets of Hanoi Medical University Hospital, Vietnam showed the superiority of the proposed method against the relevant ones in terms of clustering quality.

Coalgebraic Aspects of Context-Awareness

This paper will be both to give an in-depth analysis as well as to present the new material on the notion of context-aware computing, an idea that computing can both sense and react accordantly based on its environment. The paper formalizes context-awareness process using coalgebraic language, including the coalgebraic definition of context-awareness, bisimulation between context-awarenesses, homomorphism between context-awarenesses and context-awarenesses as coalgebras. Discussions for further development based on this approach are also given.This paper will be both to give an in-depth analysis as well as to present the new material on the notion of context-aware computing, an idea that computing can both sense and react accordantly based on its environment. The paper formalizes context-awareness process using coalgebraic language, including the coalgebraic definition of context-awareness, bisimulation between context-awarenesses, homomorphism between context-awarenesses and context-awarenesses as coalgebras. Discussions for further development based on this approach are also given.

The Energy-Aware Operational Time of Wireless Ad-Hoc Sensor Networks

Sensor networks are deployed in numerous military and civil applications, such as remote target detection, weather monitoring, weather forecast, natural resource exploration and disaster management. Despite having many potential applications, wireless sensor networks still face a number of challenges due to their particular characteristics that other wireless networks, like cellular networks or mobile ad hoc networks do not have. The most difficult challenge of the design of wireless sensor networks is the limited energy resource of the battery of the sensors. This limited resource restricts the operational time that wireless sensor networks can function in their applications. Routing protocols play a major part in the energy efficiency of wireless sensor networks because data communication dissipates most of the energy resource of the networks. This paper studies the importance of considering neighboring nodes in the energy efficiency routing problem. After showing that the routing problem that considers the remaining energy of all sensor nodes is NP-complete, heuristics are proposed for the problem. Simulation results show that the routing algorithm that considers the remaining energy of all sensor nodes improves the system lifetime significantly compared to that of minimum transmission energy algorithms. Also, the energy dissipation of neighboring nodes accounts for a considerable amount of the total energy dissipation. Therefore, a method that reduces the energy dissipation by notifying the neighboring nodes to turn off their radio when not necessary is proposed. By reducing the unnecessary energy dissipation of the neighbors, the lifetime is increased significantly.

Base Station Location -Aware Optimization Model of the Lifetime of Wireless Sensor Networks

Recently, wireless sensor networks (WSNs) have been progressively applied in various fields and areas. However, its limited energy resources is indisputably one of the weakest point that strongly affects the network’s lifetime. A WSN consists of a sensor node set and a base station. The initial energy of each sensor node will be depleted continuously during data transmission to the base station either directly or through intermediate nodes, depending on the distance between sending and receiving nodes. This paper consider determining an optimal base station location such that the energy consumption is kept lowest, maximizing the network’s lifetime and propose a nonlinear programming model for this optimizing problem. Our proposed method for solving this problem is to combine methods mentioned in [1] respectively named the centroid, the smallest total distances, the smallest total squared distances and two greedy methods. Then an improved greedy method using a LP tool provided in Gusek library is presented. Finally, all of the above methods are compared with the optimized solution over 30 randomly created data sets. The experimental results show that a relevant location for the base station is essential.

Maximizing the Lifetime of Wireless Sensor Networks with the Base Station Location

Nowadays, wireless sensor networks (WSNs) have been increasingly applied in many different areas and fields. However, one major defect of WSNs is limited energy resources, which affects the network lifetime strongly. A wireless sensor network includes a sensor node set and a base station. The initial energy of each sensor node will be depleted gradually during data transmission to the base station either directly or through other sensor nodes, depending on the distance between the sending node and the receiving node. This paper considers specifying a location for the base station such that it can minimize the consumed energy of each sensor node in transmitting data to that base station, in other words, maximizing the network lifetime. We propose a nonlinear programming model for this optimal problem. Four methods, respectively named as the centroid, the smallest total distances, the smallest total squared distances and greedy method, for finding the base station location are also presented, experimented and compared to each other over 30 data sets that are created randomly. The experimental results show that a relevant location for the base station is essential.

Energy-Aware Optimization Model in Chain-Based Routing

Sensor networks are deployed in numerous military and civil applications, such as remote target detection, weather monitoring, weather forecast, natural resource exploration and disaster management. Despite having many potential applications, wireless sensor networks still face a number of challenges due to their particular characteristics that other wireless networks, like cellular networks or mobile ad hoc networks do not have. The most difficult challenge of the design of wireless sensor networks is the limited energy resource of the battery of the sensors. This limited resource restricts the operational time that wireless sensor networks can function in their applications. Routing protocols play a major part in the energy efficiency of wireless sensor networks because data communication dissipates most of the energy resource of the networks. The above discussions imply a new family of protocols called chain-based protocols. In the protocols, all sensor nodes sense and gather data in an energy efficient manner by cooperating with their closest neighbors. The gathering process can be done until an elected node calculates the final data and sends the data to the base station. In our works, we have proposed two methods to optimize the lifetime of chain-based protocols using Integer Linear Programming (ILP) formulations. Also, a method to determine the bounds of the lifetime for any energy-efficient routing protocol is presented. Finally, simulation results verify the work in this chapter. Furthermore, previous researches assume that the base station position is randomly placed without optimization. In our works, a non convex optimization model has been developed for solving the base station location optimization problem.

Functional Stream Derivatives of Context-Awareness on P2P Networks

This paper will be both to give an in-depth analysis as well as to present the new material on the notion of context-awareness process on P2P networks, an idea that networking can both sense and react accordantly based on external actions. The paper formalizes context-awareness process using the notion of functional stream derivative, including P2P networks, context-awareness and the functional stream derivatives of context-awareness on P2P networks. A brief summary of this approach is also given.

Applying and Deploying Cyber Physical System in Monitoring and Managing Operations Under Mines and Underground Works

This paper presents results of a study on the current situation of monitoring underground gases in Vietnam, on the basis of which a model of cyber physical system will then be proposed in order to monitor and manage operations under mines and underground works. This system composes of: devices that measure Methane (CH4) [1] and Carbon monoxide (CO) [2] that are set up under mines in order to track these gases 24/7. The information received from these devices will be sent to on-ground stations and stored in the system database for collecting and managing information about gas detectors, warnings of fire and explosion, so timely warnings can be sent to workers under mines through the alarming system that is integrated in the detectors in case of unexpected incidents.

Currying Self-* Actions in Autonomic Systems

Self-* is regarded as a foundation for autonomic computing. The concepts of autonomic systems (ASs) and self-* action are considered as a basis for research on currying self-* actions. In this paper, we will specify ASs, self-* actions in ASs, product of ASs and universal properties, and then move on to consider curried self-* actions.

Heuristic Solutions for the Lifetime Problem of Wireless Sensor Networks

In [5, 7, 8] an analytical model of the lifetime problem of wireless sensor networks is developed. The solution given by the model is not practical for WSNs. Each time, there is a change in a sensor network, the solution needs to be recalculated. Also, it is difficult to build ILP solvers inside the small sensors. Furthermore, when the number of sensor nodes and CHs increases, it quickly becomes infeasible to calculate an optimum solution. As the analytical model is not able to be used to solve complicated networks, heuristic solutions are then examined that can compute the solutions for large sensor networks. Finally, the simulation results of the heuristic solutions are presented and discussed.