Steady-State Operability in Design for Dynamic Management in Realization of Networked Engineering Systems
Volume 4: 23rd Design for Manufacturing and the Life Cycle Conference; 12th International Conference on Micro- and Nanosystems, 2018
Digitization of networked engineered systems is a technology that is increasingly being adopted t... more Digitization of networked engineered systems is a technology that is increasingly being adopted to respond to changes in the market. Hence, the need for design methods to design a system adaptable to dynamic changes in the market. It is evident through a critical review of literature that current approaches for designing of networked engineering systems are neither agile nor rapidly configurable, and, at design time, usually do not have flexibility in selection and determination of the values of design parameters to lower the overall cost during the execution of networked engineering systems and simultaneously ensure that the product quality is acceptable. Accordingly, in this paper, a method, Design for Dynamic Management, for the realization of networked engineering systems is proposed. The key features of this method, in the context of Design for Dynamic Management, are adaptability and operability in the design of systems. The efficacy of the method is illustrated on a 2-D panel...
A Coverage Algorithm in 3D Wireless Sensor Networks
2006 1st International Symposium on Wireless Pervasive Computing
... This contradicts the 3. Algorithm for the 3D Coverage Problem ... the i=1~~~~~0 sensing space... more ... This contradicts the 3. Algorithm for the 3D Coverage Problem ... the i=1~~~~~0 sensing space of all the nodes in SUB(SX).8 ... 4 2. The first approach is not cost efficient and will2' consume a great amount of energy The second and .; ...
Residual muscle contraction and prosthetic socket interface force in a transtibial amputee upon the osteomyoplastic procedure — A preliminary study
2012 ISSNIP Biosignals and Biorobotics Conference: Biosignals and Robotics for Better and Safer Living (BRC), 2012
In the Transtibial Osteomyoplastic Amputation (TOA) technique, the fibular end and the tibial end... more In the Transtibial Osteomyoplastic Amputation (TOA) technique, the fibular end and the tibial end are connected to each other by a bone bridge in order to stabilize the bony anatomy of the residual limb. In addition, during the myoplasty procedure, the ends of the muscles are secured to one another and to the bony foundations to re-establish the length-tension relationship.
International journal of pavement research and technology, 2012
The Mechanistic Empirical Pavement Design Guide (MEPDG) provides three levels of input (i.e. Leve... more The Mechanistic Empirical Pavement Design Guide (MEPDG) provides three levels of input (i.e. Level 1, Level 2, and Level 3) for the design and analysis of flexible pavements. The selection of a particular level of input depends on the amount of information available to the designer and the criticality of the project. For all three input levels, the dynamic modulus (|E*|) of hot mix asphalt (HMA) is used as an important parameter to evaluate the stress-strain characteristics of an asphalt layer associated with its performance (i.e. rutting and fatigue cracking). The present study was undertaken to compare |E*| for these three levels of inputs for modified and unmodified HMA mixes. Two different mixes having a similar nominal maximum aggregate size of 19 mm were collected from the production plant. The mixes were prepared with a styrene-butadiene-styrene (SBS)-modified binder of performance grade (PG)70-28 and an unmodified binder of PG64-22. Specimens were prepared for each mix at fo...
Optimal Tracking Control of Power Converters Integrated with Variable Distortion
2020 IEEE International Conference on Environment and Electrical Engineering and 2020 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe)
In this paper, an optimal controller based on state-dependent coefficient factorization (SDCF) is... more In this paper, an optimal controller based on state-dependent coefficient factorization (SDCF) is proposed to monitor and enhance the performance of power converters under injected random noise. Power converters are becoming an essential element in many power system applications such as voltage conversion, energy storage, micro-grids, and renewable energy converters. Although several methods have been proposed for power converter control that provide a fast response and higher accuracy, few have focused on the impact of random distortion injected to the converter circuit. The proposed approach relies on remodeling the nonlinear converter dynamics as series of linear models and controlling it using an optimal tracker. The approach is implemented on a single-phase boost converter to design a state feedback controller. The results obtained show better performance, lower power losses, faster response and enhanced state observation when compared to optimal trackers that ignore random distortions.
An Artificial Neural Network based Approach to Electric Demand Response Implementation
2018 North American Power Symposium (NAPS), 2018
This paper proposes an artificial neural network based approach to implement electric demand resp... more This paper proposes an artificial neural network based approach to implement electric demand response (DR) programs. In order to maintain the continuous electricity supply, the total generated power must meet the load demand with spinning reserves for unforeseen contingencies. If a power system fails to satisfy all or part of its loads, then load curtailments cannot be avoided. However, load curtailments can be reduced or even avoided by implementing DR programs. The effectiveness of DR programs to reduce/avoid load curtailments depends on efficient and accurate identification of appropriate hourly loads for DR programs. In this work, a feed-forward artificial neural network approach is used to classify system hourly loads based on customers’ potential participation in DR programs as well as to identify the effective periods of participation. In addition, a mathematical model based on the demand-price elasticity, incentives, and penalties is developed to calculate interruptible/curtailable loads for DR programs. The proposed method is demonstrated on the IEEE reliability test system. The results of the case study show that the proposed method is effective in identifying appropriate hourly loads to implement DR programs.
Intelligent Compaction of Stabilized Subgrade of Flexible Pavement
IFCEE 2015, 2015
The long-term performance of a flexible pavement largely depends on the compaction level achieved... more The long-term performance of a flexible pavement largely depends on the compaction level achieved in different layers during construction. Traditionally, the compaction level of the subgrade is monitored through spot checking of moisture content and dry density at some discrete points. However, this type of quality control work does not cover the entire pavement and may leave under-compacted areas. These under-compacted areas could likely lead to early failure of the pavement structure. Therefore, it is necessary to develop a real-time compaction monitoring tool that can provide an accurate measurement of the compaction level of the entire pavement. Such measurements could be used to identify and remediate under- compacted areas and provide adequate support to asphalt layers constructed on top of the prepared subgrade. The application of the Intelligent Compaction Analyzer (ICA) for real-time monitoring of compaction of a stabilized subgrade is addressed in this paper. Four case studies demonstrating the successful application of the ICA are included. The compaction level of the stabilized subgrade was monitored in terms of ICA density and modulus. In each case study, it was found that ICA could estimate the compaction level with a reasonable accuracy. It was also found that the ICA modulus and nuclear density gauge (NDG) measured density exhibits a good correlation with R 2 equal to 0.73.
A Concurrent Design Exploration Method for Realizing Networked Manufacturing Systems
Volume 4: 22nd Design for Manufacturing and the Life Cycle Conference; 11th International Conference on Micro- and Nanosystems, 2017
Multistage manufacturing processes (MMPs) are networked manufacturing systems consisting of multi... more Multistage manufacturing processes (MMPs) are networked manufacturing systems consisting of multiple operational stations that have characteristics of mechanical and control systems. Common challenges in the design of MMPs are the selection of sensors and tools as this not only affects the dimensional quality of the finished product, but also influences the computational complexity in representing and analyzing the problem. Imprecise or incomplete information results in uncertainty in the models used to represent the MMP and limit the use of traditional design approaches. In this paper, an exploration method for the concurrent design (CDEM) of MMPs under uncertainty is presented wherein the attributes of tools and sensors are treated as design variables, thereby allowing flexibility in a design process. The proposed method is illustrated using an example of automotive panel stamping process. Our focus in this paper is on the method rather than the results per se.
Challenges in Engineering Devices that Promote Natural Gait in Amputees
State-of-the-art in prosthetic design for below-knee or transtibial amputees is based primarily o... more State-of-the-art in prosthetic design for below-knee or transtibial amputees is based primarily on the biomechanics of linear walking on level surfaces [1-3]. Existing foot/ankle prostheses tend to be passive devices that cannot accommodate the demands of changing user gait or changes such as surface and slope of the terrain. Limitations on gait imposed by inadequate prosthetic devices can result in musculoskeletal pain and sores that adversely affect the health of the individual [1, 4-6]. Gait asymmetry can also lead to hip/knee replacement surgeries over time. Although some designs recognize the importance of active prosthetic devices, their implementation is complicated due to lack of functional requirements that address user gait under all conditions [7-8]. Recent developments in biomimetic control have resulted in exciting new control strategies that improve the performance of complex systems with human agents [9-10]. While there have been significant advances made in surgical ...
International journal of pavement research and technology, 2012
Reclaimed Asphalt Pavement (RAP) has been widely used in the construction and rehabilitation of f... more Reclaimed Asphalt Pavement (RAP) has been widely used in the construction and rehabilitation of flexible pavements. A proper understanding of the performance of hot mix asphalt (HMA) prepared with RAP is important to ensure better and longer lasting pavements. The present study was undertaken to evaluate the effect of long-term oven (LTO) aging of HMA mixes containing RAP using the dynamic modulus (|E*|) test. Two different HMA mixes, namely Mix-1 and Mix-2, were collected from asphalt plant. Mix-1 contains performance grade (PG) 64-22 unmodified binder mixed with 25% RAP, while Mix-2 includes PG76-28 styrene-butadiene-styrene (SBS)-modified binder mixed with 15% RAP. Both mixes have the same aggregate type (primarily limestone), aggregate gradation and binder content. Specimens were compacted using a Superpave Gyratory Compactor (SGC) at four target air voids of 6%, 8%, 10% and 12% (i.e., percentage compactions of 94% to 88% of the maximum theoretical density). LTO-aging of compact...
The objective of the study is to improve Oklahoma Department of Transportation (ODOT) chip seal d... more The objective of the study is to improve Oklahoma Department of Transportation (ODOT) chip seal design and performance through introducing new criteria for the selection of cover aggregate and binder. These criteria will be based upon the recent technological advances in the characterization of aggregate shape and texture as well as aggregate-binder compatibility. The study evaluates the shape and texture-related index properties, as well as durability, of commonly used cover aggregates in chip seal programs in Oklahoma. Additionally, it will provide a methodology for inclusion of these characteristics as a metric in future chip seal specifications. The study includes both laboratory testing and construction and performance evaluation of chip seal test sections. The study is ongoing and is quantifying how well the newly developed performance-based uniformity coefficient (PUC) correlate with chip seal performance in Oklahoma, and if it should be incorporated into state chip seal spec...
In today's business environment, the trend towards more product variety and customization is unbr... more In today's business environment, the trend towards more product variety and customization is unbroken. Due to this development, the need of agile and reconfigurable production systems emerged to cope with various products and product families. To design and optimize production systems as well as to choose the optimal product matches, product analysis methods are needed. Indeed, most of the known methods aim to analyze a product or one product family on the physical level. Different product families, however, may differ largely in terms of the number and nature of components. This fact impedes an efficient comparison and choice of appropriate product family combinations for the production system. A new methodology is proposed to analyze existing products in view of their functional and physical architecture. The aim is to cluster these products in new assembly oriented product families for the optimization of existing assembly lines and the creation of future reconfigurable assembly systems. Based on Datum Flow Chain, the physical structure of the products is analyzed. Functional subassemblies are identified, and a functional analysis is performed. Moreover, a hybrid functional and physical architecture graph (HyFPAG) is the output which depicts the similarity between product families by providing design support to both, production system planners and product designers. An illustrative example of a nail-clipper is used to explain the proposed methodology. An industrial case study on two product families of steering columns of thyssenkrupp Presta France is then carried out to give a first industrial evaluation of the proposed approach.
This paper presents a hierarchical architecture for the realization of teams of intelligent auton... more This paper presents a hierarchical architecture for the realization of teams of intelligent autonomous ground vehicles called Adaptation and Learning at All Levels (AL 2). Requirements on system intelligence are translated into requirements on the system hardware and software. Recent trends in the hardware-software co-design and hardware reconfiguration that enable the realization of these requirements are then introduced and the design methodology is discussed. Examples are provided to illustrate the design methodology.
In the traditional compaction procedure of pavement subgrade, the level of compaction is checked ... more In the traditional compaction procedure of pavement subgrade, the level of compaction is checked through spot measurements of density and moisture contents at some selected locations. Such tests can leave soft spots undetected and could result in the premature failure of the pavement. In the intelligent compaction (IC) procedure, the compaction level of the entire compacted area can be estimated in real-time. The University of Oklahoma has developed one intelligent compaction tool known as Intelligent Compaction Analyzer (ICA). This paper presents two field demonstrations for evaluating the ICA in continuously measuring the dry density and modulus of stabilized subgrades. In the first study, it was demonstrated that the ICA can estimate the subgrade density comparable to Nuclear Density Gauge (NDG) measured density. The second project verified the ability of ICA in estimating the modulus of the stabilized subgrade. The ICA estimated moduli correlates well (R 2 = 0.63) with the resilient moduli. The findings from these two demonstrations suggest that the ICA is capable of continuously measuring the density or modulus during the compaction of subgrade. Such real-time estimates of the subgrade stiffness can aid roller operators obtaining better overall quality by identifying and remediating under-compacted areas during the construction process.
Uploads
Papers by sesh commuri