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Analysis Of Short Crack Growth In Particulate Composites, Ying Zhang, Tsuchin P. Chu, Ajay Mohan Mahajan, Chi Tsieh Liu Apr 2015

Analysis Of Short Crack Growth In Particulate Composites, Ying Zhang, Tsuchin P. Chu, Ajay Mohan Mahajan, Chi Tsieh Liu

Dr. Ajay Mahajan

This paper presents the analysis of the short-crack propagation and growth in particulate composite materials by using the image correlation techniques and fracture mechanics theory. The fracture mechanics model for a long crack does not work very well with short-crack propagation when the initial crack length is less than 5.1 mm (0.2 inch). In order to investigate the short crack effect, a series of tests of particulate composite specimens with long and short cracks have been performed and the results were recorded on a video tape. These test data were analyzed to determine the strain fields near the ...


Local Material Properties Meausrement Using Ultrasonic C-Scan Techniques, Dooheon Kim, Tsuchin P. Chu, Ajay Mohan Mahajan Apr 2015

Local Material Properties Meausrement Using Ultrasonic C-Scan Techniques, Dooheon Kim, Tsuchin P. Chu, Ajay Mohan Mahajan

Dr. Ajay Mahajan

Mechanical material properties of concrete specimen are evaluated locally and non-destructively using an ultrasonic C-scan system. The time of flight of the sound wave between front surface and back surface for test samples was measured. Local Young's modulus at scanning point and average Young's modulus of entire specimen are calculated. Testing techniques are developed by calibrating the transducer not only to compensate for the time delay but also to control the measurement of properties of interest, such as true density and local thickness. In order to obtain additional mechanical property, such as Poisson's ratio, the transverse velocities ...


Real-Time Measurement Of Surface Deformation Of Rotating Blades, Jay Maudlin, Ajay Mohan Mahajan, Tsuchin P. Chu Apr 2015

Real-Time Measurement Of Surface Deformation Of Rotating Blades, Jay Maudlin, Ajay Mohan Mahajan, Tsuchin P. Chu

Dr. Ajay Mahajan

This paper presents the results for the real-time measurement of surface deformation of rotating elements. A digital image correlation technique is used to estimate the surface displacements and strains. Speckle patterns are spray painted on the surface of interest and digital images taken before and during deformation caused by rotary motion. The digital image of the deformed blade is taken by freezing the speckled pattern with the help of a stroboscope. The technique provides several advantages over traditional methods in terms of obtaining whole-field deformation profiles, a non-invasive measurement scheme, and a simple and economical set-up. Results are presented for ...


Particle Swarm Optimization Approach For Maximizing The Yield Of A Coal Preparation Plant, Vishal Gupta, Hussain Unjawala, Ajay Mohan Mahajan, Manoj Mohanty Apr 2015

Particle Swarm Optimization Approach For Maximizing The Yield Of A Coal Preparation Plant, Vishal Gupta, Hussain Unjawala, Ajay Mohan Mahajan, Manoj Mohanty

Dr. Ajay Mahajan

This paper presents the use of particle swarm optimization to maximize the clean coal yield of a coal preparation plant that typically has multiple cleaning circuits that produce the same product quality so that the blend of clean coal meets the targeted product quality contraints. Particle swarm is used for the yield optimization while satisfying multiple product quality restraints. The results show a 2.73% increase in the yield can be achieved leading to additional revenue of $5,460,000 per annum for a plant producing 10 million tons of clean coal per year without significantly adding to the implementation ...


The Integrated Systems Engineering Laboratory- An Innovative Approach To Vertical Integration Using Modern Instrumentation, Ajay Mahajan, Maurice Walworth, David Mcdonald, Kevin Scmaltz Apr 2015

The Integrated Systems Engineering Laboratory- An Innovative Approach To Vertical Integration Using Modern Instrumentation, Ajay Mahajan, Maurice Walworth, David Mcdonald, Kevin Scmaltz

Dr. Ajay Mahajan

The current paradigm in engineering course instruction builds on a lecture prerequisite structure but ignores the need for a laboratory prerequisite structure. Educational quality is therefore diminished as instructors optimize specific laboratories but fail to optimize the overall program laboratory experience. This paper presents a learning environment based on modern instrumentation that forces students to use not only concepts and skills acquired from the lecture, but also actual data and models acquired from lower division laboratories, in upper division laboratories. The vertical integration occurs because students must utilize their previous laboratory work as a reference and/or building blocks as ...


Diabetic Patients Foot Care Using Smart Materials To Prevent Ulcerations/Amputations, Carrie Hahn, Ajay Mahajan, Marco P. Schoen Apr 2015

Diabetic Patients Foot Care Using Smart Materials To Prevent Ulcerations/Amputations, Carrie Hahn, Ajay Mahajan, Marco P. Schoen

Dr. Ajay Mahajan

A major cause of illness and disability in diabetic patients is complications affecting the lower limbs, particularly the feet where loss of feeling may result in ulcerations, and ultimately to partial or total amputation. Traditional remedies for this problem still remains in measuring the foot pressures and then designing a passive shoe insert that absorbs the high pressures. This process may then be repeated multiple times during the lifetime of the patient. This paper describes the conceptual design of an automatic system that monitors and controls the pressure levels in diabetic patients’ feet in real time. The scheme is based ...


High Ppeed Circuit Techniques For Network Intrusion Detection Systems (Nids), Ajay Mohan Mahajan Apr 2015

High Ppeed Circuit Techniques For Network Intrusion Detection Systems (Nids), Ajay Mohan Mahajan

Dr. Ajay Mahajan

No abstract provided.


Intelligent Sensors: An Integrated Systems Approach, Ajay Mahajan, Sanjeevi Chitikeshi, Pavan Bandhil, Lucas Utterback, Fernando Figueroa Apr 2015

Intelligent Sensors: An Integrated Systems Approach, Ajay Mahajan, Sanjeevi Chitikeshi, Pavan Bandhil, Lucas Utterback, Fernando Figueroa

Dr. Ajay Mahajan

The need for intelligent sensors as a critical component for Integrated System Health Management (ISHM) is fairly well recognized by now. Even the definition of what constitutes an intelligent sensor (or smart sensor) is well documented and stems from an intuitive desire to get the best quality measurement data that forms the basis of any complex health monitoring and/or management system. If the sensors, i.e. the elements closest to the measurand, are unreliable then the whole system works with a tremendous handicap. Hence, there has always been a desire to distribute intelligence down to the sensor level, and ...


Fiber-Optic Strain Gauge With High Resolution And Update Rate, Fernando Figueroa, Ajay Mohan Mahajan, Mohammad Sayeh, Bradley Regez Apr 2015

Fiber-Optic Strain Gauge With High Resolution And Update Rate, Fernando Figueroa, Ajay Mohan Mahajan, Mohammad Sayeh, Bradley Regez

Dr. Ajay Mahajan

An improved fiber-optic strain gauge is capable of measuring strains in the approximate range of 0 to 50 microstrains with a resolution of 0.1 microstrain. (To some extent, the resolution of the strain gauge can be tailored and may be extensible to 0.01 microstrain.) The total cost of the hardware components of this strain gauge is less than $100 at 2006 prices. In comparison with prior strain gauges capable of measurement of such low strains, this strain gauge is more accurate, more economical, and more robust, and it operates at a higher update rate. Strain gauges like this ...


Implementing High-Speed String Matching Hardware For Network Intrusion Detection Systems, Ajay Mahajan, Benfano Soewito, Sai K. Parsi, Ning Weng, Haibo Wang Apr 2015

Implementing High-Speed String Matching Hardware For Network Intrusion Detection Systems, Ajay Mahajan, Benfano Soewito, Sai K. Parsi, Ning Weng, Haibo Wang

Dr. Ajay Mahajan

This paper presents high-throughput techniques for implementing FSM based string matching hardware on FPGAs. By taking advantage of the fact that string matching operations for different packets are independent, a novel multi-threading FSM design is presented, which dramatically increases the FSM frequency and the throughput of string matching operations. In addition, design techniques for high-speed interconnect and interface circuits for the proposed FSM are also presented. Experimental results conducted on FPGA platforms are presented to study the effectiveness of the proposed techniques and explore the trade-offs between system performance, strings partition granularity and hardware resource cost.


A Genetic Algorithm Approach For Model Reference Adaptive Control Of Ionic Polymer Metal Composites, Brijesh C. Lavu, Marco P. Schoen, Ajay Mahajan Apr 2015

A Genetic Algorithm Approach For Model Reference Adaptive Control Of Ionic Polymer Metal Composites, Brijesh C. Lavu, Marco P. Schoen, Ajay Mahajan

Dr. Ajay Mahajan

Electroactive polymers undergo physical deformation to external voltage stimuli. These electrically activated polymers possess extraordinary features making them capable as lightweight sensors and actuators in manifold applications. The characteristics of applied voltage and environmental conditions, especially the moisture content surrounding the polymer, have a combined influence on the dynamical behavior of these polymers. In order to characterize these polymers under varying environmental conditions, this paper discusses the experimental procedure and modeling techniques used to derive a representative model. Ionic polymer metal composite polymers are used for this humidity relative electrodynamical study. Insight on the numerous applications of electroactive polymers as ...