Engineering Commons^™

Broadcasting With Prediction And Selective Forwarding In Vehicular Networks, Jainjun Yang, Zongming Fei

Computer Science Faculty Publications

Broadcasting in vehicular networks has attracted great interest in research community and industry. Broadcasting on disseminating information to individual vehicle beyond the transmission range is based on inter-vehicle communication systems. It is crucial to broadcast messages to other vehicles as fast as possible because the messages in vehicle communication systems are often emergency messages such as accident warning or alarm. In many current approaches, the message initiator or sender selects the node among its neighbors that is farthest away from it in the broadcasting direction and then assigns the node to rebroadcast the message once the node gets out of …

Efficient Routing For Wireless Mesh Networks Using A Backup Path, Amir Esmailpour, Nidal Nasser, Jehad Al Dallal

Electrical & Computer Engineering and Computer Science Faculty Publications

Wireless Mesh Network (WMN) has a proven record in providing viable solutions for some of the fundamental issues in wireless networks such as capacity and range limitations. WMN infrastructure includes clusters of Mobile Ad-Hoc Networks (MANETs) connected through a fixed backbone of mesh routers. The mesh network can be constrained severely due to various reasons, which could result in performance degradation such as a drop in throughput or long delays. Solutions to this problem often focus on multipath or multichannel extensions to the existing ad- hoc routing protocols. In this paper, we propose a novel solution by introducing an alternative …

Attitudes And Behaviors In Online Communities: Empirical Studies Of The Effects Of Social, Community, And Individual Characteristics, Richard Kumi

Graduate Theses and Dissertations

Online communities and communities of practice bring people together to promote and support shared goals and exchange information. Personal interactions are important to many of these communities and one of the important outcomes of personal interactions in online communities and communities of practice is user-generated content. The three essays in the current study examines behavior motivation in online communities and communities of practice to understand how Social and personal psychological factors, and user-generated influence attitudes, intentions and behaviors in online communities.

The first essay addresses two research questions. First, how does Social capital influence exchange and combination behaviors in online …

A Solar-Powered And Multi-Tiered Mesh Node For A Portable In Situ Emergency Response System, Adam Matthews

Graduate Theses and Dissertations

The aftermath of a natural disaster is typically characterized by lack of a reliable medium for dissemination of information to survivors. Current state-of-the-art emergency response systems rely on satellite radio-enabled devices, but survivors, unlike first responders, do not have access to such devices. To mitigate this problem, we present PERPETUU a solar-powered portable GIS microserver. The microserver node can be deployed in a disaster scene, and can serve maps to survivors viewable on browsers of off-the-shelf mobile systems. A key innovation in the design of the PERPETUU node is a multi-tiered hardware architecture-the system combines a low-power micro-controller, a medium-power …

Nonlinear Adaptive Diffusion Models For Image Denoising, Ajay Kumar Mandava

UNLV Theses, Dissertations, Professional Papers, and Capstones

Most of digital image applications demand on high image quality. Unfortunately, images often are degraded by noise during the formation, transmission, and recording processes. Hence, image denoising is an essential processing step preceding visual and automated analyses. Image denoising methods can reduce image contrast, create block or ring artifacts in the process of denoising. In this dissertation, we develop high performance non-linear diffusion based image denoising methods, capable to preserve edges and maintain high visual quality. This is attained by different approaches: First, a nonlinear diffusion is presented with robust M-estimators as diffusivity functions. Secondly, the knowledge of textons derived …

Dynamic Queue Management For Hospital Emergency Room Services, Kar Way Tan

Dissertations and Theses Collection (Open Access)

The emergency room (ER) – or emergency department (ED) – is often seen as a place with long waiting times and a lack of doctors to serve the patients. However, it is one of the most important departments in a hospital, and must efficiently serve patients with critical medical needs. In the existing literature, addressing the issue of long waiting times in an ED often takes the form of single-faceted queue-management strategies that are either from a demand perspective or from a supply perspective. From the demand perspective, there is work on queue design such as priority queues, or queue …

A Dynamic Programming Approach To Achieving An Optimal End State Along A Serial Production Line, Shih-Fen Cheng, Blake E. Nicholson, Marina A. Epelman, Daniel J. Reaume, Robert L. Smith

Research Collection School Of Computing and Information Systems

In modern production systems, it is critical to perform maintenance, calibration, installation, and upgrade tasks during planned downtime. Otherwise, the systems become unreliable and new product introductions are delayed. For reasons of safety, testing, and access, task performance often requires the vicinity of impacted equipment to be left in a specific “end state” when production halts. Therefore, planning the shutdown of a production system to balance production goals against enabling non-production tasks yields a challenging optimization problem. In this paper, we propose a mathematical formulation of this problem and a dynamic programming approach that efficiently finds optimal shutdown policies for …

Design And Development Of A Low-Cost Handheld Picoammeter, Malcolm Stagg

Honors Capstones

No abstract provided.

Clustering And Classification Of Multi-Domain Proteins, Neethu Shah

School of Computing: Dissertations, Theses, and Student Research

Rapid development of next-generation sequencing technology has led to an unprecedented growth in protein sequence data repositories over the last decade. Majority of these proteins lack structural and functional characterization. This necessitates design and development of fast, efficient, and sensitive computational tools and algorithms that can classify these proteins into functionally coherent groups.

Domains are fundamental units of protein structure and function. Multi-domain proteins are extremely complex as opposed to proteins that have single or no domains. They exhibit network-like complex evolutionary events such as domain shuffling, domain loss, and domain gain. These events therefore, cannot be represented in the …

Improving Patient Length-Of-Stay In Emergency Department Through Dynamic Queue Management, Kar Way Tan, Hoong Chuin Lau, Francis Chun Yue Lee

Research Collection School Of Computing and Information Systems

Addressing issue of crowding in an Emergency Department (ED) typically takes the form of process engineering or single-faceted queue management strategies such as demand restriction, queue prioritization or staffing the ED. This work provides an integrated framework to manage queue dynamically from both demand and supply perspectives. More precisely, we introduce intelligent dynamic patient prioritization strategies to manage the demand concurrently with dynamic resource adjustment policies to manage supply. Our framework allows decision-makers to select both the demand-side and supply-side strategies to suit the needs of their ED. We verify through a simulation that such a framework improves the patients' …

Adaptive Computer‐Generated Forces For Simulator‐Based Training, Expert Systems With Applications, Teck-Hou Teng, Ah-Hwee Tan, Loo-Nin Teow

Research Collection School Of Computing and Information Systems

Simulator-based training is in constant pursuit of increasing level of realism. The transition from doctrine-driven computer-generated forces (CGF) to adaptive CGF represents one such effort. The use of doctrine-driven CGF is fraught with challenges such as modeling of complex expert knowledge and adapting to the trainees’ progress in real time. Therefore, this paper reports on how the use of adaptive CGF can overcome these challenges. Using a self-organizing neural network to implement the adaptive CGF, air combat maneuvering strategies are learned incrementally and generalized in real time. The state space and action space are extracted from the same hierarchical doctrine …

A Simple Integration Of Social Relationship And Text Data For Identifying Potential Customers In Microblogging, Guansong Pang, Shengyi Jiang, Dongyi Chen

Research Collection School Of Computing and Information Systems

Identifying potential customers among a huge number of users in microblogging is a fundamental problem for microblog marketing. One challenge in potential customer detection in microblogging is how to generate an accurate characteristic description for users, i.e., user profile generation. Intuitively, the preference of a user’s friends (i.e., the person followed by the user in microblogging) is of great importance to capture the characteristic of the user. Also, a user’s self-defined tags are often concise and accurate carriers for the user’s interests. In this paper, for identifying potential customers in microblogging, we propose a method to generate user profiles via …

Zero-Sum Two-Player Game Theoretic Formulation Of Affine Nonlinear Discrete-Time Systems Using Neural Networks, Shahab Mehraeen, Travis Dierks, S. Jagannathan, Mariesa L. Crow

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the nearly optimal solution for discrete-time (DT) affine nonlinear control systems in the presence of partially unknown internal system dynamics and disturbances is considered. The approach is based on successive approximate solution of the Hamilton-Jacobi-Isaacs (HJI) equation, which appears in optimal control. Successive approximation approach for updating control and disturbance inputs for DT nonlinear affine systems are proposed. Moreover, sufficient conditions for the convergence of the approximate HJI solution to the saddle point are derived, and an iterative approach to approximate the HJI equation using a neural network (NN) is presented. Then, the requirement of full knowledge …

Solutions To Finite Horizon Cost Problems Using Actor-Critic Reinforcement Learning, Ivo Grondman, Hao Xu, Sarangapani Jagannathan, Robert Babuska

Electrical and Computer Engineering Faculty Research & Creative Works

Actor-critic reinforcement learning algorithms have shown to be a successful tool in learning the optimal control for a range of (repetitive) tasks on systems with (partially) unknown dynamics, which may or may not be nonlinear. Most of the reinforcement learning literature published up to this point only deals with modeling the task at hand as a Markov decision process with an infinite horizon cost function. In practice, however, it is sometimes desired to have a solution for the case where the cost function is defined over a finite horizon, which means that the optimal control problem will be time-varying and …

Adjust Decision-Making Targets Based On Psychological Thresholds, Jian Liu, Shun Xiang Wu, Si Feng Liu, Qiao Wang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper study the impact of psychological thresholds (PTs) on the decision maker's (DM's) decision target when making decision. A new approach of decision making is proposed in this paper. First, we construct criterion expected functions according to three different types of criteria: profit type, cost-type and intermediate-type, respectively. Then, we calculate the local degree of satisfaction (LDS) of each object when PTs exists, in order to adjust the initial decision target to make up new decision table. Later, by weighting the criteria reaching the DM's degree of satisfaction (DS) along with information aggregation algorithm, we obtain the overall satisfaction …

Finite Horizon Stochastic Optimal Control Of Uncertain Linear Networked Control System, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, finite horizon stochastic optimal control issue has been studied for linear networked control system (LNCS) in the presence of network imperfections such as network-induced delays and packet losses by using adaptive dynamic programming (ADP) approach. Due to an uncertainty in system dynamics resulting from network imperfections, the stochastic optimal control design uses a novel adaptive estimator (AE) to solve the optimal regulation of uncertain LNCS in a forward-in-time manner in contrast with backward-in-time Riccati equation-based optimal control with known system dynamics. Tuning law for unknown parameters of AE has been derived. Lyapunov theory is used to show …

Decision Trees To Model The Impact Of Disruption And Recovery In Supply Chain Networks, Loganathan Ponnanbalam, L. Wenbin, Xiuju Fu, Xiaofeng Yin, Zhaoxia Wang, Rick S. M. Goh

Research Collection School Of Computing and Information Systems

Increase in the frequency of disruptions in the recent times and their impact have increased the attention in supply chain disruption management research. The objective of this paper is to understand as to how a disruption might affect the supply chain network - depending upon the network structure, the node that is disrupted, the disruption in production capacity of the disrupted node and the period of the disruption - via decision trees. To this end, we first developed a 5-tier agent-based supply chain model and then simulated it for various what-if disruptive scenarios for 3 different network structures (80 trials …

An Agent-Based Simulation Approach To Experience Management In Theme Parks, Shih-Fen Cheng, Larry Junjie Lin, Jiali Du, Hoong Chuin Lau, Pradeep Reddy Varakantham

Research Collection School Of Computing and Information Systems

In this paper, we illustrate how massive agent-based simulation can be used to investigate an exciting new application domain of experience management in theme parks, which covers topics like congestion control, incentive design, and revenue management. Since all visitors are heterogeneous and self-interested, we argue that a high-quality agent-based simulation is necessary for studying various problems related to experience management. As in most agent-base simulations, a sound understanding of micro-level behaviors is essential to construct high-quality models. To achieve this, we designed and conducted a first-of-its-kind real-world experiment that helps us understand how typical visitors behave in a theme-park environment. …

Tonescale Compression For Electroluminescent Display, Michael E. Miller, Christopher J. White

AFIT Patents

A method for controlling an electroluminescent display to produce an image for display that has reduced luminance to reduce burn-in on the display while maintaining visible contrast, includes providing the electroluminescent (EL) display having a plurality of EL emitters, the luminance of the light produced by each EL emitter being responsive to a respective drive signal; receiving a respective input image signal for each EL emitter; and transforming the input image signals to a plurality of drive signals that have a reduced peak frame luminance value but maintains contrast in the displayed image to reduce burn-in by adjusting the drive …

A Novel Defense Mechanism Against Web Crawler Intrusion, Alireza Aghamohammadi

Master's Theses and Doctoral Dissertations

Web robots also known as crawlers or spiders are used by search engines, hackers and spammers to gather information about web pages. Timely detection and prevention of unwanted crawlers increases privacy and security of websites. In this research, a novel method to identify web crawlers is proposed to prevent unwanted crawler to access websites. The proposed method suggests a five-factor identification process to detect unwanted crawlers. This study provides the pretest and posttest results along with a systematic evaluation of web pages with the proposed identification technique versus web pages without the proposed identification process. An experiment was performed with …

The Development Of It And Telnet And Its Impact In Business Security (Non Security), Musa Tahiraj

UBT International Conference

During the years, the people are more hungry for faster doing processes and works. There always is high possibility for loss business and markets by different attacks in different layers. In this paper is presented which are the challenges faced with information security on businesses during the rapid development IT and Telnet. This challenge requires stable technology, the standard platform and especially policies and rules for implementation security steps through those rapid changes in technology. In the paper are presented some of statistical review about the causes of information damage, which are advantages and weaknesses using new information technology. At …

Benchmarks For Hybrid Modelling, Andreas Koerner, Felix Breitenecker

UBT International Conference

Hybrid Modelling is getting more and more important in technical and natural sciences. In these fields very complex systems and processes have to be simulated and therefore proper models must be developed. For complex systems different model structures for dynamical systems are available. One of the important model structures regarding complex dynamical systems are hybrid models. A hybrid model consists of several dynamical models and a state diagram where each state is described by a differential algebraic equation (DAE). This paper deals with benchmarks out of different fields of applications of this modelling approach. The first benchmark is an electrical …

Comparison Of Emotion Evaluation Perception Using Human Voice Signals Of Robots And Humans, Vesna Kirandziska, Nevena Ackovska

UBT International Conference

Emotion perception is the process of perceiving other people’s emotions. It can be based on their facial expression, movement, voice and other biosignals people emit. The evaluation of human’s emotion is one characteristic of emotions. One of the research areas in Robotics is adapting humanistic behavior in robots. Today many robots are constructed. Some of them can even perceive emotions. In this paper a custom built emotion aware robot that perceives emotion evaluation is used to investigate the similarity and differences of the robot's and human's emotion perception. Voice signals from real human were recorded and the information for the …

Comparative Performance Simulation Of Dsdv Aodv And Dsr Manet Protocols In Ns2, Erion Cana

UBT International Conference

Mobile Ad hoc Networks (MANET) are self-configured and infrastructure less networks with autonomous mobile nodes. Due to the high flexibility, these kind of networks are heavily used in rescue operations, military missions etc. Many routing protocols for this kind of networks exist. This article presents a comparative and quantitative performance study of DSDV, AODV and DSR routing protocols using different simulation models in NS2. Performance metrics like PDR, E2E Delay and Throughput are analyzed under varying network, traffic and mobility parameters like number of nodes, traffic flows, mobility speed and pause time. Results show that AODV outperforms DSDV and DSR …

More-Space – A Simulation Tool For University Room Management, Nicole Nagele-Wild, Š. Emrich, S. Tauböck, Felix Breitenecker, Niki Popper, D. Wiegand

UBT International Conference

As proposed in various studies, educational facilities hold a high potential yield for improvement of room utilization. The goal of the project “MoreSpace” at Vienna University of Technology (TU Vienna) was to develop a hybrid modeling approach which helps to increase the efficiency of the university’s space utilization. Besides coupling of Discrete Event Simulation (DEVS), Agent-based (AB) methods and Cellular Automata (CA), successful deployment of such a model requires a thorough integration within the peripheral system. Which in turn leads to preconditions that have to be met, (e.g. by input - data, visualization of results, dissemination, etc.). This paper covers …

Cleaner Robot In The Cloud – "Cleo", Krenare Pireva, Kushtrim Dragusha, Bertan Karahoda

UBT International Conference

With the upcoming of cloud computing technology, the robots doesn’t have to act anymore on their own but they can learn from the experiences of other robots. The main idea of this proposal is how to share knowledge between heterogeneous robots and how to move the processing power from robots to the cloud via cloud computing. A demonstration is thought to be realized using clean robots and the services of cloud computing platform RoboEarth. The orientation and position coordinates of the cleaner robot can easily be calculated by using the encoder and electronic compass. The ultrasonic distance sensor will scan …

The Impact Of Technology In Orientation Aid, Ines Bula, Edin Bula, Muzafer Shala

UBT International Conference

Statistic states that 285 million people are estimated to be visually impaired worldwide: 39 million are blind and 246 have low vision. About 90% of the world's visually impaired people live in developing countries. Taking in consideration that Mechatronics is a methodology used for the optimal design of electromechanical products, and by combining technologies that are available to us we can develop a very useful tool that blind people and people with sight problems can change their lives. Combining smart phones and digital camera there are possibilities to build smart glasses which will give information to blind people. In this …

Impact Of Counterbalance Mass On Torsional Vibrations Of Crankshaft, Asllan Hajderi, Drakuli Lumi

UBT International Conference

In the present study is shown how to change the main indicators of vibrations of crankshaft, in case of changing its masses. In the study it was taken the crankshaft of diesel engine with 4 cylinders in line with 5 main journals. To study the torsional vibration of the crankshaft system, the first it is carried the construction of equivalent reduced scheme with five discs connected to four flexible shafts. Results show that the reduced inertia moments of disks for the case with counterbalances grow to 24%. Free frequency and vibration forms, is calculated by using Holxer-Tole method. Results show …

Comparison Of Local Image Descriptors For Plant Identification From Leaf Images, Lameski Petre, Zdravevski Eftim, Kulakov Andrea

UBT International Conference

In this paper we present several descriptors used for the task of Plant recognition based on the images of leaves. The set of descriptors include texture based descriptors, fractal descriptors as well as some of the state of the art descriptors for image retrieval and object recognition in images. The descriptors are generated from the leaf images taken from single leaves on homogenous background. The descriptors are then used for training classifiers from a dataset of leaf images. The comparison of the obtained results will be presented in this paper.

Swarm Intelligence As An Optimization Technique, Alma Bregaj

UBT International Conference

Optimization techniques inspired by swarm intelligence have become increasingly popular during the last years. Swarm intelligence is based on nature-inspired behaviours and is successfully applied to optimisation problems in a variety of fields. The advantage of these approaches over traditional techniques is their robustness and flexibility. These properties make swarm intelligence a successful design paradigm for algorithms that deal with increasingly complex problems. In this paper I am focused on the comparison between different swarm-based optimisation algorithms and I have presented some examples of real practical applications of these algorithms.