Tutorial Dialog in an Equation Solving Intelligent Tutoring System

This thesis makes a contribution to Intelligent Tutoring Systems (ITS) architectures. A new intelligent tutoring system is presented for the domain of solving linear equations. This system is novel, because it is the first intelligent equation-solving tutor that combines a cognitive model of the domain with a model of dialog-based tutoring. The tutorial model is novel because it is based on the observation of an experienced human tutor and captures tutorial strategies specific to the domain of equation-solving. In this context, a tutorial dialog is the equivalent of breaking down problems into simpler steps and then asking new questions to the student before proceeding to the next navigational step. The resulting system, named E-tutor, was compared, via a randomized controlled experiment, to an algebra ITS similar to the“Cognitive Tutor by Carnegie Learning, Inc®. The Cognitive Tutor can provide traditional model-tracing feedback and buggy messages to students, but does not engage students in dialog. Preliminary results using a very small sample size, i.e., teaching equation solving to 15 high school students, showed that E-Tutor with dialog capabilities performed better than E-tutor without dialog. This result showed an effect size of 0.4 standard deviations for overall learning by condition. This set of preliminary results, though not statistically significant, shows promising opportunities to improve learning performance by adding tutorial dialog capabilities to ITSs. However, significant further validation is required, specifically, adding greater numbers and variations of the work to our sample size, before this approach can be deemed successful. The system is available at www.wpi.edu/~leenar/E-tutor

Stability, vibration and passive damping of partially restrained imperfect columns

A theoretical and experimental study of slender tubular columns for possible use in space structures is conducted in the presence of partial rotational end restraints. Explicit formulas are derived for computing the buckling load and the lowest natural frequency of perfectly straight uniform elastic members with rotational end restraints possessing linear moment-rotation characteristics. An exact solution in the form of a transcendental equation, and a numerical solution using second-order finite-differences are also presented. The presence of an initial imperfection is also incorporated into the numerical procedure. Vibration tests are conducted on an imperfect tubular steel member in the absence of an axial load. A damping concept consisting of a string-mass assembly is explored. Three passive damping configurations involving combinations of three lead shots were investigated. The three lead shot configurations provided considerably greater damping than the single lead shot

Future Community-Based Ecotourism (CBET) development

Ecotourism is an alternative form of tourism and is usually confused with natural and cultural tourism.CBET is fast becoming a popular biodiversity conservation tool that develops and benefits the local community. Based on the context of conservation theory and practice, Community-Based Ecotourism (CBET) is a form of community-based natural resource management. However, a sustainable CBET development through Community Capacity Building (CCB)programs is not something that it easily achievable. Local community’s capacity varies from one culture to another. It takes a high level of community participation, in order for it to come to a level where the community members themselves are motivated to participate and contribute to the development of the program. This fully qualitative research involved 15 respondents from the community of Kg. Selai, Bekok in Johor, Malaysia. The result show there are five factors that sustained the ecotourism development based for Orang Asli Community in Kg. Selai, namely, existing CBET development, past CBET development, local community participation in planning stage of tourism, local participation in implementation stage of tourism and participation in nature conservation

A Design of Coreless Permanent Magnet Axial Flux Generator for Low Speed Wind Turbine

Most of the available generators in the market are a high speed induction generator which requires high rotational speed and electricity to generate a magnetic field. However, there are very few low-speed generators that exist in the market that available for small energy resources. This paper aims to design and simulate a Coreless Permanent Magnet Axial Flux Generator (PMAFG) for low speed wind turbine. An axial flux generator was designed to have a low speed rotation using a permanent magnet of the type Neodymium Iron Boron (NdFeB). The model was examined with excel to data analyzed. Coreless PMAFG is a generator that is enabled to turn on energy at low speeds. The chosen model was Double Rotor - Single Stator (12 Slots 8 Poles) using Infolytica Magnet software. Finite Element Method (FEM) was employed to analyze the phenomena of the magnetic flux. The test was simulated using static rotation method, which rotated every 3 degrees at 350 rpm with 100 turns and 10, 30, 50, 80 and 100 Ohm of load variations. Compare to the calculation of the design, results of the simulation in terms of voltage, current, power and efficiency had been met with only very small error

Sidelobe level correction for parabolic antennas radiation pattern measurements in quasi-far-field conditions

A method and formulae for correction of the sidelobe level of the radiation pattern of a high gain antenna when measured in the Fresnel region are presented. After a thorough analysis of a large number of different cases, trend curves have been computed and an empirical formula has been derived, which allows the correction of the measured values of the sidelobes when the measurement range is below or around the far-field distance

A Comparative Predicting Stock Prices using Heston and Geometric Brownian Motion Models

This paper presents a novel approach to predicting stock prices using technical analysis. By utilizing Ito's lemma and Euler-Maruyama methods, the researchers develop Heston and Geometric Brownian Motion models that take into account volatility, interest rate, and historical stock prices to generate predictions. The results of the study demonstrate that these models are effective in accurately predicting stock prices and outperform commonly used statistical indicators. The authors conclude that this technical analysis-based method offers a promising solution for stock market prediction

An optimal allocation of UPFC and transient stability improvement of an electrical power system: IEEE-30 buses

Recently, the expansion process of electrical networks has become crucial with the development of electrical systems. One of the active solutions to progress the performance of an electrical system is the usage of flexible AC transmission system (FACTS). As a new generation of telecommunications and power electronics technology, FACTS has provided a new viewpoint to increase the bearing capacity, better control the grid, and reduce costs. The unified power flow controller had a multi-purpose unit that could command the scenario of providing or consuming the power components and maintaining the bus voltage. The study's novelty resided in presenting a modified particle swarm optimization algorithm-based software system and applied a Newton-Raphson load flow solution to get the best solutions for optimal allocation of unified power flow controllers (UPFC). This study has focused on the functions of the UPFC electrical system with corresponding effects on transient stability. MATLAB software (Simulink/code) and excel sheet were performed on IEEE 30 buses as a case study. It has been shown the effectiveness of UPFC with fast response and autonomous command on the flow of power components. The dynamic response for stability improvement for some network buses had been verified to ensure the robustness of UPFC during a sudden disturbance in electrical load. The case study results illustrate that the number of UPFC increased with load increased by (14% and 21%)