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California Polytechnic State University, San Luis Obispo

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2009

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Articles 31 - 60 of 122

Full-Text Articles in Engineering

Cost-Benefit Analysis Of Error Reduction For Complex Systems, Robert A. Mcdonald Sep 2009

Cost-Benefit Analysis Of Error Reduction For Complex Systems, Robert A. Mcdonald

Aerospace Engineering

The cost-benefit tradeoff of analysis fidelity in complex systems analysis has been posed as an optimization problem providing quantitative guidance for investment in improving analysis. A nonlinear constrained optimizer to solve this problem has been integrated into an error tradeoff environment providing an intuitive tool for the decision maker to consider investment in fidelity at the same time as design decisions are considered. An example demonstrates the efficacy of the improved interface to enable fidelity improvement investment decisions.


Multidisciplinary Design Optimization Of An Extreme Aspect Ration Hale Uav, Bryan Morrisey, Robert A. Mcdonald Sep 2009

Multidisciplinary Design Optimization Of An Extreme Aspect Ration Hale Uav, Bryan Morrisey, Robert A. Mcdonald

Aerospace Engineering

Development of High Altitude Long Endurance (HALE) aircraft systems is part of a vision for a low cost communications/surveillance capability. Applications of a multi payload aircraft operating for extended periods at stratospheric altitudes span military and civil genres and support battlefield operations, communications, atmospheric or agricultural monitoring, surveillance, and other disciplines that may currently require satellite-based infrastructure. The central goal of this research was the development of a multidisciplinary tool for analysis, design, and optimization of HALE UAVs, facilitating the study of a novel configuration concept. Applying design ideas stemming from a unique WWII-era project, a "pinned wing" HALE aircraft …


Work In Progress - A Mixed-Methods Approach To Developing An Instrument Measuring Engineering Students' Positive Ethical Behavior, Mathew A. Holsapple, Cynthia J. Finelli, Donald D. Carpenter, Trevor S. Harding, Janel A. Sutkus Sep 2009

Work In Progress - A Mixed-Methods Approach To Developing An Instrument Measuring Engineering Students' Positive Ethical Behavior, Mathew A. Holsapple, Cynthia J. Finelli, Donald D. Carpenter, Trevor S. Harding, Janel A. Sutkus

Materials Engineering

Ethics education and the drive to produce ethical professional engineers is an important focus of one body of research on engineering education. This research often defines the positive outcome of ethics education as students and professional engineers choosing not to engage in unethical behavior. This paper discusses a portion of a larger research project and details efforts to identify and validate a definition of ethical behavior that includes the decision to engage in a positive behavior, defined as a service to a larger community. Through a series of interviews and focus groups with engineering administrators, faculty, and students, the authors …


A Modification To The Group Delay And Simulated Annealing Technique For Characterization Of Peripheral Nerve Fiber Size Distributions For Non-Deterministic Sampled Data, Robert B. Szlavik Sep 2009

A Modification To The Group Delay And Simulated Annealing Technique For Characterization Of Peripheral Nerve Fiber Size Distributions For Non-Deterministic Sampled Data, Robert B. Szlavik

Biomedical Engineering

The ability to determine the characteristics of peripheral nerve fiber size distributions would provide additional information to clinicians for the diagnosis of specific pathologies of the peripheral nervous system. Investigation of these conditions, using electro-diagnostic techniques, is advantageous in the sense that such techniques tend to be minimally invasive yet provide valuable diagnostic information. One of the principal electro-diagnostic tools available to the clinician is the nerve conduction velocity test. While the peripheral nerve conduction velocity test can provide useful information to the clinician regarding the viability of the nerve under study, it is a single parameter test that yields …


A Novel Approach For Analyzing Severe Crash Patterns On Multilane Highways, Anurag Pande, Mohamed Abdel-Aty Sep 2009

A Novel Approach For Analyzing Severe Crash Patterns On Multilane Highways, Anurag Pande, Mohamed Abdel-Aty

Civil and Environmental Engineering

This study presents a novel approach for analysis of patterns in severe crashes that occur on mid-block segments of multilane highways with partially limited access. A within stratum matched crash vs. non-crash classification approach is adopted towards that end. Under this approach crashes serve as units of analysis and it does not require aggregation of crash data over arterial segments of arbitrary lengths. Also, the proposed approach does not use information on non-severe crashes and hence is not affected by under-reporting of the minor crashes. Random samples of time, day of week, and location (i.e., milepost) combinations were collected for …


Variability Within Irrigated Fields, Charles M. Burt, Byron Clark Sep 2009

Variability Within Irrigated Fields, Charles M. Burt, Byron Clark

BioResource and Agricultural Engineering

In agricultural production and research, it is common to represent fields as uniform areas. For example, fertilizers, soil amendments, and other inputs have traditionally been applied uniformly (or as uniformly as possible) based on estimated needs for the field as a whole (or as an “average”).

Of course, it is also recognized that fields are not truly uniform with respect to soil characteristics, uniformity of applied water, pest pressures, fertility needs, crop growth and yield, and other characteristics. With the emergence and refinement of variable rate application technology, many growers now attempt to maximize returns by “prescribing” variable amounts of …


Traffic Signal Control With Swarm Intelligence, David Renfrew, Xiao-Hua Yu Aug 2009

Traffic Signal Control With Swarm Intelligence, David Renfrew, Xiao-Hua Yu

Electrical Engineering

Traffic signal control is an effective way to regulate traffic flow to avoid conflict and reduce congestion. The ACO (Ant Colony Optimization) algorithm is an optimization technique based on swarm intelligence. This research investigates the application of ACO to traffic signal control problem. The decentralized, collective, stochastic, and self-organization properties of this algorithm fit well with the nature of traffic networks. Computer simulation results show that this method outperforms the conventional fully actuated control, especially under the condition of high traffic demand.


Electrocardiogram (Ecg) Signal Modeling And Noise Reduction Using Wavelet Neural Networks, Suranai Poungponsri, Xiao-Hua Yu Aug 2009

Electrocardiogram (Ecg) Signal Modeling And Noise Reduction Using Wavelet Neural Networks, Suranai Poungponsri, Xiao-Hua Yu

Electrical Engineering

Electrocardiogram (ECG) signal has been widely used in cardiac pathology to detect heart disease. In this paper, wavelet neural network (WNN) is studied for ECG signal modeling and noise reduction. WNN combines the multi-resolution nature of wavelets and the adaptive learning ability of artificial neural networks, and is trained by a hybrid algorithm that includes the adaptive diversity learning particle swarm optimization (ADLPSO) and the gradient descent optimization. Computer simulation results demonstrate this proposed approach can successfully model the ECG signal and remove high-frequency noise.


I/Q Compensation Of Frequency Dependent Response Mismatch In A Pair Of Analog Low-Pass Filters, Peter Kiss, Vladimir I. Prodanov Aug 2009

I/Q Compensation Of Frequency Dependent Response Mismatch In A Pair Of Analog Low-Pass Filters, Peter Kiss, Vladimir I. Prodanov

Electrical Engineering

Frequency dependent I/Q imbalance in real I/Q filter pairs compensation may be performed using a simple compensation module, placed in the receiver/transmitter chain, with a gain adjustment coefficient and a delay adjustment coefficient. The gain adjustment coefficient may be determined by amplitude measurements conducted at a selected frequency near the center of the band-pass region of the filters. The delay adjustment coefficient may be determined by phase measurements conducted at a selected frequency near the edge of the band-pass region of the filters. Statistical analysis may be used to determine types of real filters that are better suited for the …


A Computer-Based Approach To Material And Process Selection Using Sustainability And Ecological Criteria, Manocher Djassemi Aug 2009

A Computer-Based Approach To Material And Process Selection Using Sustainability And Ecological Criteria, Manocher Djassemi

Industrial Technology and Packaging

Decision on selecting a material or process for a particular product is a common task in product engineering and facility planning. Such decision may have a significant impact on entire product life cycle including raw material acquisition, product manufacture, use, disposal, and environment. Traditional factors for decision making are economical, functional and aesthetical properties of the product. However, the issues of sustainability and environmental impact of materials and manufacturing processes have gained a growing attention in recent decade by general population as well as academicians and industrial practitioners. The objective of this study is to explore a software tool for …


Reinvestigation Of Liquefaction And Nonliquefaction Case Histories From The 1976 Tangshan Earthquake, Robb E.S. Moss, Robert Kayen, Liyuan Tong, Songyu Liu, Guojun Cai, Jiaer Wu Aug 2009

Reinvestigation Of Liquefaction And Nonliquefaction Case Histories From The 1976 Tangshan Earthquake, Robb E.S. Moss, Robert Kayen, Liyuan Tong, Songyu Liu, Guojun Cai, Jiaer Wu

Civil and Environmental Engineering

A field investigation was carried out to retest liquefaction and nonliquefaction sites from the 1976 Tangshan earthquake in the People's Republic of China (PRC). These sites were carefully investigated in 1978/1979 using standard penetration test (SPT) and cone penetration test (CPT) equipment; however the CPT measurements are obsolete because of the now nonstandard cone that was used at the time. In 2007 a modern cone was mobilized to retest 18 select sites that are particularly valuable because they experienced intense ground shaking, have high fines content, and are classified as nonliquefaction sites. Of the sites reinvestigated and carefully processed, 13 …


Using Conditional Inference Forests To Identify The Factors Affecting Crash Severity On Arterial Corridors, Abhishek Das, Mohamed Abdel-Aty, Anurag Pande Aug 2009

Using Conditional Inference Forests To Identify The Factors Affecting Crash Severity On Arterial Corridors, Abhishek Das, Mohamed Abdel-Aty, Anurag Pande

Civil and Environmental Engineering

Introduction

The study aims at identifying traffic/highway design/driver-vehicle information significantly related with fatal/severe crashes on urban arterials for different crash types. Since the data used in this study are observational (i.e., collected outside the purview of a designed experiment), an information discovery approach is adopted for this study.

Method

Random Forests, which are ensembles of individual trees grown by CART (Classification and Regression Tree) algorithm, are applied in numerous applications for this purpose. Specifically, conditional inference forests have been implemented. In each tree of the conditional inference forest, splits are based on how good the association is. Chi-square test statistics …


Hardware Acceleration Of Multi-View Face Detection, Jungok Cho, Bridget Benson, Ryan Kastner Jul 2009

Hardware Acceleration Of Multi-View Face Detection, Jungok Cho, Bridget Benson, Ryan Kastner

Electrical Engineering

This paper presents a parallelized architecture for hardware acceleration of multi-view face detection. In our architecture, the multi-view face detection system generates rotated image windows and their integral image windows for each classifier which perform parallel classification operations to detect non-upright (rotated) and non-frontal (profile) faces in the images. We use the training data from OpenCV to detect the frontal and profile faces based on the Viola and Jones algorithm. The proposed architecture for multi-view face detection has been designed using Verilog HDL and implemented in a Xilinx Virtex-5 FPGA. Its performance has been measured and compared with a Jones' …


Parallelized Architecture Of Multiple Classifiers For Face Detection, Junguk Cho, B. Benson, S. Mirazaei, R. Kastner Jul 2009

Parallelized Architecture Of Multiple Classifiers For Face Detection, Junguk Cho, B. Benson, S. Mirazaei, R. Kastner

Electrical Engineering

This paper presents a parallelized architecture of multiple classifiers for face detection based on the Viola and Jones object detection method. This method makes use of the AdaBoost algorithm which identifies a sequence of Haar classifiers that indicate the presence of a face. We describe the hardware design techniques including image scaling, integral image generation, pipelined processing of classifiers, and parallel processing of multiple classifiers to accelerate the processing speed of the face detection system. Also we discuss the parallelized architecture which can be scalable for configurable device with variable resources. We implement the proposed architecture in Verilog HDL on …


New Pressure Sensitive Device To Measure And Predict Package Drops, Sher Paul Singh, Jay Singh, Young Paek Jul 2009

New Pressure Sensitive Device To Measure And Predict Package Drops, Sher Paul Singh, Jay Singh, Young Paek

Industrial Technology and Packaging

Pressurex®, a tactile pressure sensor film which is manufactured by Sensor Product Inc. (East Hanova, NJ, USA), is one of the emerging materials that is convenient for measurements of the strength of pressure and pressure distribution profile between two contacting surfaces without any instrumentation. It immediately reveals impact distribution and magnitude based on intensity and dispersion of color. The intensity of this color is proportional to the amount of force applied allowing the user to actually quantify the stress characteristics across the impact surface. The objective of this paper was to examine free fall drop test results using …


Packaging Trends For Bottled Water, N. Noble, L. Paul, C. Mcminimee, M. Mallett, Jay Singh Jul 2009

Packaging Trends For Bottled Water, N. Noble, L. Paul, C. Mcminimee, M. Mallett, Jay Singh

Industrial Technology and Packaging

The Journal of Applied Packaging Research(JAPR) is an international forum for the dissemination of research papers, review articles, tutorials and news about innovative or emerging technologies for the packaging industry. In an effort to introduce research conducted by packaging students to the academics and industry professionals and to provide an outlet for these future stewards of the packaging industry to experience the world of publishing, JAPR, occasionally includes such work in its issues.

Bottled water is drinking water packaged generally in plastic bottles and regulated by national and local agencies. The Beverage Marketing Corporation defines the bottled water market …


Bit Error Rate, Power And Area Analysis Of Multiple Fpga Implementations Of Underwater Fsk, Ying Li, Bridget Benson, Ryan Kastner, Xing Zhang Jul 2009

Bit Error Rate, Power And Area Analysis Of Multiple Fpga Implementations Of Underwater Fsk, Ying Li, Bridget Benson, Ryan Kastner, Xing Zhang

Electrical Engineering

There has been an increasing interest in creating short-range, low data-rate underwater wireless sensor networks for scientific marine exploration and monitoring. However, the lack of an inexpensive, low-power, underwater acoustic modem is preventing the proliferation of these sensor networks. Thus, we are building an underwater acoustic modem that considers cost and power at every level, from the analog electronics, to the modulation scheme, to the hardware platform. In this paper, we use reconfigurable devices to explore the design space of our modulation scheme – Frequency Shift Keying (FSK) – to select an implementation that provides the lowest power and area …


Safety Evaluation Of Multilane Arterials In Florida, Mohamed Abdel-Aty, Prem Chand Devarasetty, Anurag Pande Jul 2009

Safety Evaluation Of Multilane Arterials In Florida, Mohamed Abdel-Aty, Prem Chand Devarasetty, Anurag Pande

Civil and Environmental Engineering

Resurfacing is one of the more common construction activities on highways. While its effect on riding quality on any type of roadway is obviously positive; its impact on safety as measured in terms of crashes is far from obvious. This study examines the safety effects of the resurfacing projects on multilane arterials with partially limited access. Empirical Bayes method, which is one of the most accepted approaches for conducting before–after evaluations, has been used to assess the safety effects of the resurfacing projects. Safety effects are estimated not only in terms of all crashes but also rear-end as well as …


Drop Impact Reliability Of Edge-Bonded Lead-Free Chip Scale Packages, Andrew Farris, Jianbiao Pan, Albert Liddicoat, Michael Krist, Nicholas Vickers, Brian J. Toleno, Dan Maslyk, Dongkai Shangguan, Jasbir Bath, Dennis Willie, David A. Geiger Jul 2009

Drop Impact Reliability Of Edge-Bonded Lead-Free Chip Scale Packages, Andrew Farris, Jianbiao Pan, Albert Liddicoat, Michael Krist, Nicholas Vickers, Brian J. Toleno, Dan Maslyk, Dongkai Shangguan, Jasbir Bath, Dennis Willie, David A. Geiger

Industrial and Manufacturing Engineering

This paper presents the drop test reliability results for edge-bonded 0.5 mm pitch lead-free chip scale packages (CSPs) on a standard JEDEC drop reliability test board. The test boards were subjected to drop tests at several impact pulses, including a peak acceleration of 900 Gs with a pulse duration of 0.7 ms, a peak acceleration of 1500 Gs with a pulse duration of 0.5 ms, and a peak acceleration of 2900 Gs with a pulse duration of 0.3 ms. A high-speed dynamic resistance measurement system was used to monitor the failure of the solder joints. Two edge-bond materials used in …


Development Of A Reusable Aerospike Nozzle For Hybrid Rocket Motors, Patrick Lemieux Jun 2009

Development Of A Reusable Aerospike Nozzle For Hybrid Rocket Motors, Patrick Lemieux

Mechanical Engineering

The Department of Mechanical Engineering at the California Polytechnic State University, San Luis Obispo, has developed an innovative program of experimental research and development on hybrid rocket motors (where the fuel and the oxidizer are in different phases prior to combustion). One project currently underway involves the development of aerospike nozzles for such motors. These nozzles, however, are even more susceptible to throat ablation than regular converging-diverging nozzles, due the nature of their flow expansion mechanism. This paper presents the result of a recent development project focused on reducing throat ablation in hybrid rocket motor nozzles. Although the method is …


Teaching Sustainability In Cal Poly Electrical And Computer Engineering Programs, David Braun, Art Maccarley, John Oliver Jun 2009

Teaching Sustainability In Cal Poly Electrical And Computer Engineering Programs, David Braun, Art Maccarley, John Oliver

Electrical Engineering

No abstract provided.


Comparison Of Overset Grid And Grid Deformation Techniques Applied To 2-Dimensional Naca Airfoils, Charles M. Hoke, Robert K. Decker, Russell M. Cummings, David R. Mcdaniel, Scott A. Morton Jun 2009

Comparison Of Overset Grid And Grid Deformation Techniques Applied To 2-Dimensional Naca Airfoils, Charles M. Hoke, Robert K. Decker, Russell M. Cummings, David R. Mcdaniel, Scott A. Morton

Aerospace Engineering

This paper documents a comparison of overset grid and grid deformation schemes applied to flapped and non-flapped NACA airfoil configurations in order to determine the relative accuracy and computational efficiency of each method. This study is part of a larger effort to use computational fluid dynamics to perform moving control surface calculations. Three different cases, using both overset and deformed grids, are considered, including: a) lift and moment comparison of a quasi-steady, non-flapped 0012 airfoil, b) lift and moment comparison of a dynamically pitching non-flapped 0012 airfoil, and c) lift comparison of a dynamic pitching and oscillating flapped 0012 airfoil. …


Application Of Volterra Functions To X-31 Aircraft Model Motion, United States Air Force Academy, Russell M. Cummings Jun 2009

Application Of Volterra Functions To X-31 Aircraft Model Motion, United States Air Force Academy, Russell M. Cummings

Aerospace Engineering

Recent advances towards an efficient computational method for accurately determining the stability and control characteristics of an aircraft are discussed and critiqued. The present approach with greatest promise is to reduce the number of high-fidelity CFD simulations by using Volterra functions Reduced Order Modeling. This type of reduced order model is a predictive model which has a unique training maneuver -a unit impulse. The advantage of such an approach is the fast prediction of the aerodynamic characteristics of an aircraft. This article presents the results of application of the Volterra functions ROM for prediction of linear movement of a 2D …


Mode Pattern Analysis Of Gallium Nitride-Based Laser Diodes, Xiaomin Jin, Sean Jobe, Simeon Trieu, Benafsh Husain, Jason Flickinger, Bei Zhang, Tao Dai, Xiang-Ning Kang, Guo-Yi Zhang Jun 2009

Mode Pattern Analysis Of Gallium Nitride-Based Laser Diodes, Xiaomin Jin, Sean Jobe, Simeon Trieu, Benafsh Husain, Jason Flickinger, Bei Zhang, Tao Dai, Xiang-Ning Kang, Guo-Yi Zhang

Electrical Engineering

In this paper, we present an analysis of gallium nitride (GaN) quantum-well (QW) laser diode (LD) by numerical simulation. Here we discuss three aspects that are crucial to our analysis. First, the transverse mode pattern is studied, and our current GaN diode laser structure is discussed with optical waveguide mode analysis. Then we compare the QW design of the laser and maximize laser modal gain. Finally, we report the influence of the electron block (e-block) layer on lasing performance of our design.


A Simple, Yet Effective, Demonstration Of Polymeric Mechanical Behavior, Lanny Griffin, Jeffrey Swab Jun 2009

A Simple, Yet Effective, Demonstration Of Polymeric Mechanical Behavior, Lanny Griffin, Jeffrey Swab

Biomedical Engineering

Developing an appreciation for the mechanical behavior of polymers materials in a lecture mode can be challenging for students if they have not bad the benefit of a laboratory experience . We have developed a simp le demonstration of thermoplastic polymeric behav ior using low-density polyethylene bags. The demonstration illustrates strengthening, rate effects, and directionality of strengthening and stiffness. Following the demonstration, students are better ab le to articulate the influence of structure, properties, processing , and performance as it applies to thermoplastic polymers.


Video Technology For Interuniversity Collaboration In A Geotechnical Engineering Laboratory, James Hanson Jun 2009

Video Technology For Interuniversity Collaboration In A Geotechnical Engineering Laboratory, James Hanson

Civil and Environmental Engineering

Advanced video technology was used to incorporate multi-component (inter-university and university-industry) collaborations in geotechnical engineering laboratory courses. The project was conducted between California Polytechnic State University (California), Auburn University (Alabama), and Nippon Koei Co., Ltd. (Japan). Synchronous video conferencing and asynchronous video communications were used between the partners. The conferencing activities included guest lectures and exchange of assignments. New assignments developed in the study included role-playing whereby one class acted as a client on a project that was ordering geotechnical testing to be completed by the students at the other university acting as a consulting firm. New assignments also included …


Rfid Tag Readability Issues With Palletized Loads Of Consumer Goods, Jay Singh, Eric Olsen, Keith Vorst, K. Tripp Jun 2009

Rfid Tag Readability Issues With Palletized Loads Of Consumer Goods, Jay Singh, Eric Olsen, Keith Vorst, K. Tripp

Industrial Technology and Packaging

Radio Frequency Identification (RFID) is an automatic identification technology, relying on storing and remotely retrieving data using devices called RFID tags. This technology is being used in enterprise supply chain management-related applications to improve the efficiency of inventory tracking and management. However, this technology has not been able to realize its promised potential because of several factors, such as lack of congruous worldwide standards, privacy issues and less than perfect read rates in supply chain applications. This research aimed to evaluate the readability issues commonly faced by tagged cases of palletized consumer products. The variables studied in this research were …


The Effects Of Thermal Annealing On The Obliquely Deposited Ag–Ge–S Thin Films, F. Wang, W. P. Dunn, M. Jain, C. De Leo, N. Vicker, Richard N. Savage, Xiaomin Jin, S. Mamedov, P. Boolchand Jun 2009

The Effects Of Thermal Annealing On The Obliquely Deposited Ag–Ge–S Thin Films, F. Wang, W. P. Dunn, M. Jain, C. De Leo, N. Vicker, Richard N. Savage, Xiaomin Jin, S. Mamedov, P. Boolchand

Materials Engineering

Obliquely deposited thin films of ternary Ag–Ge–S glasses are characterized in this work. Thin films are fabricated in a vacuum thermal evaporator at different evaporation angles and examined by Raman spectroscopy. The Raman mode frequency of GeS4 corner-sharing (CS) structure of the as-deposited films display a red-shift as a function of Ag content due to reduced global connectivity, and therefore decreased network stress. Film thickness of normally deposited thin films is significantly less when compared against obliquely deposited ones. Sulfur-ring (S8) modes are observed in thin films but not in corresponding bulk material. Thermal annealing of thin …


Modeling And Simulation Of Photovoltaic Water Pumping System, Taufik, Akihiro Oi, Makbul Anwari, Mohammad Taufik May 2009

Modeling And Simulation Of Photovoltaic Water Pumping System, Taufik, Akihiro Oi, Makbul Anwari, Mohammad Taufik

Electrical Engineering

This paper presents modeling of a simple but efficient photovoltaic water pumping system. The system employs maximum power point tracker (MPPT). Two MPPT algorithms, subsystems and control methods will be modeled and simulated using Matlab and Simulink with actual irradiance data. Simulation results will be presented in terms of performance parameters such as total energy produced and total volume of water pumped per day. The results further validate that MPPT can significantly improve efficiency and performance of PV water pumping system compared to the system without MPPT.


Performance Analysis Of Shunt Reactive Power Compensators, Taufik, Emili Schaefer, Makbul Anwari, Mohammad Taufik May 2009

Performance Analysis Of Shunt Reactive Power Compensators, Taufik, Emili Schaefer, Makbul Anwari, Mohammad Taufik

Electrical Engineering

This paper offers comparative solutions for utility companies to solve the problem of voltage flicker in distribution systems. The solutions entail provision of shunt reactive compensation. Two solutions will be explored: the shunt capacitor and the Static VAR Compensator (SVC). Both solutions are modeled and simulated using PSCAD. Results will be compared by analyzing their performance when subjected to changes on the system, and problems that arise when connected to the system.